Digital Commons Network^™

A 4,000 Year Pollen Record Of Vegetation Changes, Sea Level Rise, And Hurricane Disturbance In Atchafalaya March Of Southern Louisiana, Xinyu Zhou

LSU Historical Dissertations and Theses

Sediment cores from the Atchafalaya Marsh in southern Louisiana were intensively studied by means of pollen and loss-on-ignition analyses to reconstruct the history of late-Holocene environmental changes and hurricane strikes in the area. The data indicate that the coring site was occupied by a fresh marsh about 4000 years ago. Afterwards, the fresh marsh was replaced by a brackish marsh in the following 400 years. The marsh became a salt marsh in response to sea level rise beginning 3250 yr BP. During 2800-1200 yr BP, the study site became an estuarine environment inundated by sea water as a result of …

Join In The Dance: Didacticism In Jane Austen's Pride And Prejudice, Lisa Morales

LSU Historical Dissertations and Theses

The importance of didacticism in Jane Austen’s Pride and Prejudice may sometimes be overlooked in an effort to be entertained by the fairy-tale essence of her work. This is unfortunate since Pride and Prejudice offers a rich critique of eighteenth-century English society, as well as heralds the beginning of a new form of novel writing. This new form of novel writing includes a vision of an autonomous heroine who exercises freedom from patriarchal society and the “marriage market.” Austen’s ironic didacticism in Pride and Prejudice highlights hypocrisy and contradiction, and in so doing, mock social expectations. It is through her …

Synthesis Of Novel Amino Acids And 310- And Alpha-Helical Alpha, Alpha-Disubstituted Amino Acid Rich Antimicrobial Peptides, Thomas Scott Yokum

LSU Historical Dissertations and Theses

Amphipathic peptides rich in α, α-disubstituted amino acids (ααAAs) were synthesized and examined for antimicrobial activity and helix preference in various solvent systems. Also, a series of polar, ααAAs were synthesized for incorporation into helical peptides and a red-shifted tryptophan analog was synthesized as a fluorescent probe.

A series of short, amphipathic, 3₁₀- and α-helical peptides containing 50 to 80 percent ααAAs was synthesized. Various combinations of 1-aminocyclohexane-lcarboxylic acid, α-aminoisobutyric acid, and 4-aminopiperidine-4-carboxylic acid were incorporated using preformed acid fluorides. In vitro testing revealed that most of these peptides show direct antibacterial activity against E. coli and …

Sand Body Geometry Of The Wax Lake Outlet Delta Atchafalaya Bay, Louisiana, Susan Majersky Fitzgerald

LSU Historical Dissertations and Theses

Deltas forming in Atchafalaya Bay, L-ouisiana, are the result of delta switching by the Mississippi River. The larger Lower Atchafalaya River delta has been heavily manipulated by dredging for navigation, but the Wax Lake Outlet delta is largely undisturbed and an excellent example of a 'bayhead' delta. Combining stratigraphy, aerial photography and digital terrain model data sets, the developmental history of this delta is presented. The Wax Lake Outlet delta is comprised of a typical upward-coarsening sequence, although its prodelta unit is extremely limited. Its plan-view form is typical of deltas developing in low-energy, unstratified, shallow basins. Early developmental processes …

Aspects Of Searching And Tunneling Behavior In Resource Utilization By The Formosan Subterranean Termite, Coptotermes Formosanus Shiraki., Justin Carl Hedlund

LSU Historical Dissertations and Theses

Formosan subterranean termites, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), were acclimated with different masses of pine or no wood (control) and then allowed access to a thin sand filled tunneling chamber. As available pine increased, termite survival and food consumption increased but search tunnel volume decreased. Increased food size resulted in termites excavating fewer exploratory tunnels due to decreases in secondary and tertiary branch tunnels. An increase in food size also decreased the total length of a search tunnel network, due to decreases in primary and secondary branch order lengths. Search tunnel networks had proportionally more length devoted to primary tunnels …

United States Foreign Policy And Media Coverage Of Uzbekistan: A Case Study., Mardon Nigmatovich Yakubov

LSU Historical Dissertations and Theses

This study reviews the impact of U.S. political interests on media coverage of Uzbekistan, a Central Asian republic which became independent after the breakup of the Soviet Union. A content analysis of coverage from 1991 to 1996 in the New York Times, Washington Post, and Los Angeles Times was compared to American government documents and pronouncements on Uzbekistan. Striking similarities between U.S. policy towards Uzbekistan and the negative interpretation of events appearing in American newspapers were found. The democracy and human rights agendas advanced by U.S. officials apparently prompted editors and reporters to focus more on these subjects, while overlooking …

Effects Of Selected Polycyclic Aromatic Hydrocarbons On Cell Proliferation, Protein Phosphorylation, And Intracellular Calcium Concentration In Lepomis Macrochirus., Helen Runnels Connelly

LSU Historical Dissertations and Theses

Polycyclic aromatic hydrocarbons (PAH) have been demonstrated to affect signal transduction in higher vertebrates. In this research, the freshwater species of fish, Lepomis macrochirus (bluegill) was used to test the effects of a 14-day diet of PAH on lymphocyte signal transduction. PAH tested included: 2-aminoanthracene (2-AA), 2-methylnaphthalene (2-MN), 9,10-dimethylanthracene (9,10-DMA), and a mixture of these three compounds (MIX). Individual compounds were tested at a total PAH dose of 3.1 $\pm$ 0.01mg over the 14 day period. The MIX diet was a total PAH dose of 0.13 $\pm$ 0.01mg 2-AA, 0.19 + 0.01mg 9,10-DMA, and 0.22 $\pm$ 0.02mg 2-MN over the …

Urban Effects On Precipitation In The Southern United States Of America., Youngeun Choi

LSU Historical Dissertations and Theses

Of the many weather conditions influenced by urban areas, precipitation is one of the most controversial and unsolved elements in characterizing the urban climate. The purpose of this dissertation was to identify anomalies in precipitation totals and frequencies due to urban effects and to evaluate whether certain meteorological conditions or seasons have more apparent effects. The five largest cities in the south-central United States were selected: Houston; Dallas; San Antonio; New Orleans; and Memphis. It was assumed that simple spatial analysis can detect urban effects on precipitation over and downwind of the city with a localized maximum. Trend surface analysis …

Reproductive Isolation Between Two Species Of Topminnow, Fundulus Olivaceus And F. Euryzonus., Thomas Allen Blanchard

LSU Historical Dissertations and Theses

Fundulus olivaceus and F. euryzonus are sister species that commonly occur syntopically in the Amite and Tangipahoa River drainages in Louisiana and Mississippi. Although the habitats of the two species are quite similar, and the timing of their reproductive activity overlaps extensively, no natural hybrids between them have been documented. I examined physiological, as well as behavioral, factors that could potentially serve as effective isolating mechanisms between them. The courtship and spawning behaviors of the two species were relatively generalized and showed a number of similarities. Under forced mating conditions in which females were allowed to associate with heterospecific males …

The Interactions Among The Subunits Of The Mcrbc Restriction System In E. Coli., Loganayaki Ganesh

LSU Historical Dissertations and Theses

The McrBC system of Escherichia coli K12 restricts DNA containing modified cytosines within specific sites. The modified cytosines recognized may be 5-hydroxymethylcytosine, N$\sp4$-methylcytosine or 5-methylcytosine. In the mcrBC operon, the mcrB gene is expressed to produce the McrB$\sb{\rm L}$ protein (51 kDa) and the McrB$\sb{\rm S}$ protein (33kDa), which is translated from an inframe internal translation start site and lacks the N-terminal 161 amino acids of the long product. The McrC protein is a 39kDa protein and is required for the cleavage of most methylated substrates. Using a MalE-McrB$\sb{\rm L}$ fusion protein, the endonucleolytic McrB$\sb{\rm L}$ subunit was shown to …

Assessing Applicant "Fit" Within The Selection Process: Which Interviewer Perceptions Matter?, Dawn Ebe Haptonstahl

LSU Historical Dissertations and Theses

The research literature has noted that organizations are moving beyond simply hiring individuals with the necessary knowledge, skills, and abilities (KSAs) that fulfill the requirements of the job--employers are also looking for people who can fit in with a particular work group or even an entire organization. This study tested an exploratory model that predicted recruiter selection decisions from their evaluations of applicants' person-job (P-J), person-group (P-G), and person-organization (P-O) fit. The model also postulated that P-G and P-O fit would be predicted by the perceived congruence (similarity) of work values between applicants and groups/organizations, Hypotheses were field-tested with 64 …

Intraspecific Variation In Three Marsh Grasses In Response To Increased Flooding And Salinity., Jeannine Marie Lessmann

LSU Historical Dissertations and Theses

Intraspecific variation in response to moderate levels of flooding and salinity stress was identified in Spartina patens, S. alterniflora, and Panicum hemitomon. This analysis enabled genotypes of each species to be selected for desired traits to enhance their function in restored systems, such as increased belowground biomass to stabilize soil substrates or increased aboveground biomass to enhance sedimentation. It was also determined that increased flood tolerance conferred a greater advantage for plant growth at moderate stress levels than did increased salt tolerance. However, this growth advantage was overridden by high salinity stress, and was greatly reduced by excessive flooding stress. …

Evolutionary Effects Of Irradiation In Cataclysmic Variables., Patrick Joseph Mccormick

LSU Historical Dissertations and Theses

We developed a simple stellar computational model consisting of two concentric polytropic shells in order to investigate compact binary evolution. In this thesis we focus the investigation on the effects of irradiation on the orbital evolution of cataclysmic variables (CVs). In these systems, when the companion is illuminated by a fraction of the accretion luminosity, the orbital evolution consists of irradiation-driven limit cycles on thermal timescales. These cycles are superimposed on the secular evolution toward shorter periods due to systemic angular momentum losses. When the irradiation instability is enhanced by consequential angular momentum losses $j\sb{\rm CAML}$ the net effect is …

The Socialization Of Indian Scientific Writers Into Western Scientific Discourse Communities., Sumita Roy

LSU Historical Dissertations and Theses

This research studies the socialization of Indian science writers into western discourse communities. More specifically, it seeks to identify the writing problems that beginner Indian science writers face and the strategies that they adopt in overcoming them while writing dissertations or research articles. Primary information was gathered by interviewing 11 Indian graduate students and 17 faculty members from India (West Bengal) and the USA on the basis of a five-page questionnaire. Respondents were classified into three groups according to their places of training and writing skills. Three to five sets of rough drafts from each group were studied to note …

Pest Status Of The Fall Armyworm, Spodoptera Frugiperda (J. E. Smith), On Conventional And Transgenic Cotton Expressing The Bacillus Thuringiensis Cryia (C) Delta-Endotoxin: Development, Survival, And Host-Strain Influence., John Joseph Adamczyk Jr

LSU Historical Dissertations and Theses

The pest status of the fall armyworm, Spodoptera frugiperda (J. E. Smith), including development and survival on conventional and transgenic Bacillus thuringiensis (Bt) cotton and host-strain influences, was examined in laboratory and field studies. Neonates (1st instars) were fed leaves from conventional (cv. DP 5415 and cv. DP 5690) and transgenic Bt (cv. NuCOTN 33$\rm\sp{B}$ and cv. NuCOTN 35$\rm\sp{B})$ cotton. There were no significant differences $(P>0.05)$ between cultivars in larval mortality and survival to the pupal and adult stages. However, times to pupation and adult eclosion were significantly longer $(P<0.05)$ for larvae fed transgenic Bt cotton compared to conventional cotton. In addition, larvae weighed significantly less $(P<0.05)$ when fed transgenic Bt cotton compared to conventional cotton. A study was conducted to determine when cotton bolls become tolerant to fall armyworm injury. Fifth instars were caged individually on bolls of various ages from conventional (cv. DP 5415) and transgenic Bt (cv. NuCOTN 33$\rm\sp{B})$ cotton to define the period of boll susceptibility to larval injury. For DP 5415 bolls, there was no significant linear relationship $(P>0.05)$ describing larval mortality or successful boll penetration as …

Structural Characterization Of Beta Carbonic Anhydrases From Higher Plants., Michael H. Bracey

LSU Historical Dissertations and Theses

It is the goal of this dissertation research to reveal some aspects of the physical nature of spinach carbonic anhydrase as a representative $\beta$CA using the techniques of sequence comparison, molecular biology, and biophysics. Though both $\alpha$ and $\beta$ carbonic anhydrases are zinc dependent metalloenzymes, it is clear that the two isoforms do not adopt the same mechanism for coordinating the active site metal. While $\alpha$CA binds zinc through three histidine ligands, $\beta$CA cannot due to a lack of evolutionarily conserved histidines. Instead, the $\beta$ family has adopted a ligand scheme incorporating a single histidine and two cysteines. This has …

An Analytical Approach To A Tree-Farm Wetland Study., Robert Cunninghame Davidge

LSU Historical Dissertations and Theses

Wetland delineation is important because federal and local government regulations limit permissible uses of wetlands. Federal delineation regulations are based upon the use of a manual jointly agreed upon by EPA, USACOE, and NRCS. The manual provides for classification of land as either wetland or non-wetland based upon the 3 criteria of soil, vegetation, and hydrology. No provision is made for gradation between categorical wetland and categorical non-wetland. Controversy has sometimes developed between landowners and environmentalists as to proper wetland classification; some delineations have been considered arbitrary. The analytical method of wetland appraisal provides a means of assigning continuous numerical …

Evaluation Of The Toxicological Consequences Of Dietary Exposure To Individual Classes Of Polycyclic Aromatic Hydrocarbons Or A Mixture In The Fischer-344 Rat., Mary Durand Boudreau

LSU Historical Dissertations and Theses

There is special concern about the potential health effects of by-products released into the environment after combustion or conversion of fossil fuels. Polycyclic aromatic hydrocarbons (PAH), while initially released largely into the atmosphere, are subsequently deposited in soil and water and on foods. Although the significance of PAH contamination with regard to environmentally caused diseases and cancer in humans is difficult to estimate, it is suggested that the potential hazards may be underestimated. In an effort to understand the potential adverse health effects of PAHs, a comprehensive study was undertaken to determine the metabolic fate of selected PAHs as individual …

An Investigation Of The Relationship Between Teachers' Orientations In Reading Process And Instruction: Four Case Studies., Carrice Lou Cummins

LSU Historical Dissertations and Theses

The beliefs that teachers hold about how children learn are often reflected in the instructional practices they use to help children become readers. The purpose of this study was threefold: (a) to identify teachers' beliefs regarding how reading takes place and how reading develops, (b) to examine the instructional reading practices implemented in teachers' classrooms, and (c) to explore the relationships between teachers' theoretical beliefs and their instructional practices in providing appropriate reading instruction. Qualitative methods informed this study by providing case studies of four primary grade teachers, giving detailed accounts of their theoretical beliefs--process and instruction. Two of the …

Marginal Employment In The United States: 1971-1993., Nicole Thomson Flynn

LSU Historical Dissertations and Theses

In this dissertation, I examine trends in production and the concomitant demographic transformation of the labor force, in the context a series of economic cycles since 1969. Using these three forces as a backdrop, I first consider changes in employment hardship and the forces contributing to underemployment during periods following economic recessions. Then, I examine differences between men and women for employment outcomes. Next, to explain hardship during these periods, I include important demographic and geographic factors related to underemployment. Finally, I examine the impact of labor market context on individual outcomes. Based on the transformation of work, I explain …

The Optimal Implementation Of On-Line Optimization For Chemical And Refinery Processes., Xueyu Chen

LSU Historical Dissertations and Theses

On-line optimization is an effective approach for process operation and economic improvement and source reduction in chemical and refinery processes. On-line optimization involves three steps of work as: data validation, parameter estimation, and economic optimization. This research evaluated statistical algorithms for gross error detection, data reconciliation, and parameter estimation, and developed an open-form steady state process model for the Monsanto designed sulfuric acid process of IMC Agrico Company. The plant model was used to demonstrate improved economics and reduced emissions from on-line optimization and to test the methodology of on-line optimization. Also, a modified compensation strategy was proposed to improve …

A Knowledge-Based System For Reliability-Centered Maintenance In The Chemical Industry., Daniel Jesus Fonseca

LSU Historical Dissertations and Theses

An innovative new framework for the implementation of reliability centered maintenance (RCM) in industrial settings was developed and implemented during this study. Fuzzy reasoning algorithms were designed to evaluate and assess the likelihood of equipment failure mode precipitation and aggravation. Furthermore, an alternative to the traditional RCM decision tree for prioritizing equipment failure modes was defined through the development of an approximate reasoning scheme. This priority scheme not only takes into account the relevancy of failure modes on local and product effects, but also their possibility of occurrence, as well as associated negative consequences on adjacent machinery. The new RCM …

Parallelization And Implementation Of Approximate Root Isolation For Nonlinear System By Monte Carlo., Ebrahim Khosravi

LSU Historical Dissertations and Theses

This dissertation solves a fundamental problem of isolating the real roots of nonlinear systems of equations by Monte-Carlo that were published by Bush Jones. This algorithm requires only function values and can be applied readily to complicated systems of transcendental functions. The implementation of this sequential algorithm provides scientists with the means to utilize function analysis in mathematics or other fields of science. The algorithm, however, is so computationally intensive that the system is limited to a very small set of variables, and this will make it unfeasible for large systems of equations. Also a computational technique was needed for …

The Effect Of Pulmonary Infection (Actinobacillus Pleuropneumoniae), Endotoxin And Dexamethasone On Enrofloxacin Pharmacokinetic Parameters In Swine., Lynn O. Post

LSU Historical Dissertations and Theses

Efficacy studies are often done on diseased animals while pharmacokinetic studies are done on healthy animals. Disease models are inherently difficult to standardize because of the many variables associated with measuring pharmacokinetic parameters in abnormal animals. Information derived from pharmacokinetic studies with diseased animals could be useful to determine if therapeutic doses of a drug or antimicrobial becomes less effective or toxic due to changes in distribution and clearance. The objectives of this study were to: characterize a pulmonary infection model in swine using Actinobacillus pleuropneumoniae; evaluate the pharmacokinetic changes associated with the pulmonary infection model and dexamethasone after the …

Leisure-Time Physical Activity As A Moderator Of The Association Between Stress And Depression Among Low-Income Primary Care Female Population., Isabel Cristina Scarinci

LSU Historical Dissertations and Theses

The present study used a longitudinal design in an attempt to answer the following questions: (a) what is the prevalence of sedentary lifestyle in a low-income primary care female population? (b) does minor stress predict depressive symptoms after controlling for major stress? and (c) does leisure-time physical activity moderate the association between stress and depressive symptoms? The sample included 150 randomly selected adult female patients recruited from primary care clinics at a public hospital in the state of Louisiana. This sample consisted predominantly of uninsured, African American, low-income, middle-aged females. The results indicated that prevalence of sedentary lifestyle (58%) was …

Gaining And Controlling Access To The Arena: Stories Of Ties In A Technological Dispute., Tobias Albert Ten Eyck

LSU Historical Dissertations and Theses

This is a study of the stories told about distribution of resources and structural constraints which operate within newspaper arenas that were experienced by reporters and sources involved in coverage of food irradiation between 1987 and 1996 at two regional newspapers (Louisiana and Florida). Using an unstructured interview instrument, I conducted interviews with 40 sources and 12 newspaper reporters, which I used to construct a framework in which to show how cultural, economic and social capital are used for getting and blocking action in the newspaper arenas. These interviews show that while cultural capital was the most prominent type of …

Albert Camus's Reconstruction Of Symbolic Reality: Exile, Judgment, And Kingdom., Peter Alan Petrakis

LSU Historical Dissertations and Theses

Throughout his life, Albert Camus was deeply concerned with problems of language and representation. Often mislabeled an existentialist or philosopher of the absurd, his skepticism of modern rationality has been well recorded. Yet despite considerable scholarly attention, a satisfactory understanding of Camus's thoughts on language has not been achieved. This essay is an effort to rectify the situation by carefully exploring Camus's use and understanding of symbols. By first gleaning a theory of symbolization from the philosophical works of Ernst Cassirer, Eric Voegelin, and Paul Ricoeur, and then comparing it to Camus's writings on myth, symbols, and narrative, it is …

Gendered Experiences Of Public Accounting Firms: Organizational Commitment And Intentions To Leave., Harriet Lynn Stallworth

LSU Historical Dissertations and Theses

The under representation of female public accountants in the upper echelons of public accounting organizations is recognized as problematic by both these firms and the accounting profession. The problem is confounded by women's higher turnover rate at each organizational level within these firms. The purpose of this study is to examine women's and men's experiences of the public accounting work environment in order to provide some insight into why women are more likely to leave these firms. The research questions to be addressed are (1) whether, and specifically, how, do males' and females' experiences of the public accounting work environment …

Creativity And The Cathartic Moment: Chaos Theory And The Art Of Theatre., Robert E. Brooks

LSU Historical Dissertations and Theses

This dissertation investigates the potential applications of the scientific paradigm known as "chaos theory" in the examination of dramatic theory. By illuminating the limitations of traditional Newtonian physics and Euclidean geometry, chaos theory conveys philosophical implications that transcend the scientific and provide suitable tools for describing cultural and artistic phenomena. These implications include emphasis on unpredictability, interaction and feedback, qualitative rather that quantitative analyses, and a nonlinear, continuous, even holistic perspective of systems traditionally viewed as dischotomous (such as order and disorder or part and whole). This study examines several standard works of dramatic theory, concentrating on the relationship of …

Logistic Regression And Item Response Theory: Estimation Item And Ability Parameters By Using Logistic Regression In Irt., Necati Engec

LSU Historical Dissertations and Theses

The purpose of this study was to investigate the utility of logistic regression procedures as a means of estimating item and ability parameters in unidimensional and multidimensional item response theory models for dichotomous and polytomous data instead of IRT models. Unlike the IRT models, single logistic regression model can be easily extended from unidimensional models to multidimensional models, from dichotomous response data to polytomous response data and the assumptions such as all slopes are the same and intercept is zero are unnecessary. Based on the findings of this study, the following preliminary conclusions can be drawn: Item and ability parameters …