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LSU Historical Dissertations and Theses

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A Study Of Ferruccio Busoni's Transcriptions Of Six Organ Chorale Preludes By Johannes Brahms., Carmen Scialla Jan 1992

A Study Of Ferruccio Busoni's Transcriptions Of Six Organ Chorale Preludes By Johannes Brahms., Carmen Scialla

LSU Historical Dissertations and Theses

Ferruccio Busoni's piano arrangements of six of Brahms's Eleven Chorale Preludes, Op. 122, are among the least known of his transcriptions. Published in 1897, they have remained overshadowed by his more popular transcriptions of the organ works of Bach. Maurice Hinson stated that "Busoni arranged some of the most pianistic of the set"; continuing, Hinson observed that problems encountered in the originals, such as bringing out inner voices and achieving a satisfactory legato, are more easily solved on the piano.$\sp1$. Referring to Busoni's own writings on transcribing as found in the appendices to his edition of Bach's Well-Tempered Clavier, this …

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Monopoles And Confinement In Lattice-Gauge Theory., Vandana Singh Jan 1992

Monopoles And Confinement In Lattice-Gauge Theory., Vandana Singh

LSU Historical Dissertations and Theses

The mechanism by which quarks, believed to be the fundamental constituents of matter, are prevented from existing in the free state is still unknown. The phenomenon of quark confinement is one of the fundamental problems in physics. One of the most viable candidates for a hypothesis of confinement is the dual superconductor mechanism that likens quark confinement to the Meissner effect in superconductors. The peculiarities of quark interactions make a numerical approach to the subject a necessity, and therefore, much of the work in this area has been done through the methods of lattice gauge theory, with the simplicities afforded …

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Attitudes Toward International Harmonization Efforts: A Cross-Cultural Study., M. Aileen Smith Jan 1992

Attitudes Toward International Harmonization Efforts: A Cross-Cultural Study., M. Aileen Smith

LSU Historical Dissertations and Theses

The last two decades have seen a significant increase in the number and size of multinational corporations and a growing global investment environment. Linked to that growth has been a call for standards that produce accounting information that is capable of crossing national boundaries. One of the groups of professional elites that have addressed the call for harmonized international accounting standards is the International Accounting Standards Committee (IASC). The IASC objective (IASC 1988, 1) states that it will "work generally for the improvement and harmonization of regulations, accounting standards and procedures ... " To address such a goal, the IASC …

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The Molecular Systematics Of Unitunicate, Perithecial Ascomycetes., Joseph William Spatafora Jan 1992

The Molecular Systematics Of Unitunicate, Perithecial Ascomycetes., Joseph William Spatafora

LSU Historical Dissertations and Theses

Maximum parsimony analysis of partial sequences from the small subunit ribosomal DNA (ssrDNA) rejects the monophyly of unitunicate, perithecial ascomycetes (pyrenomycetes). The genera Kathistes, Pyxidiophora and Subbaromyces are separated from a large clade of relatively derived pyrenomycetes. This derived pyrenomycete clade is supported by a bootstrap confidence level of 100% and a decay index of $>$10 steps, and contains two subclades, A and B. Subclade A comprises the orders Clavicipitales, Hypocreales, Microascales and the genus Ceratocystis; subclade B consists of the Diaporthales, Sordariales, Xylariales and the genus Ophiostoma. The Clavicipitales is a sister taxon to the Hypocreales, which consists …

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A Study On The Aquic Conditions Of Two Natraqualfs In The Coastal Plain Of Louisiana., Ariel Alejandro Szogi Jan 1992

A Study On The Aquic Conditions Of Two Natraqualfs In The Coastal Plain Of Louisiana., Ariel Alejandro Szogi

LSU Historical Dissertations and Theses

This study had the purposes of investigating the aquic conditions of two selected Natraqualfs to define the relationship between wetness and morphological properties and prediction of major soil processes. The proposed criteria for aquic conditions as defined by the International Committee on Aquic Conditions (ICOMAQ) were identified by: (i) presence of redoximorphic features, and (ii) measurement of saturation and reduction. They were used to locally verify morphological inferences used to predict the aquic conditions. Morphological properties and laboratory analysis were used to predict the periodicity and duration of saturation and reduction. Soil and ground water analyses were used to understand …

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Using Independence Training To Teach Independent Living Skills To Visually Impaired Children And Youth., Marie E. Taras Jan 1992

Using Independence Training To Teach Independent Living Skills To Visually Impaired Children And Youth., Marie E. Taras

LSU Historical Dissertations and Theses

Two groups of students with visual impairments were taught various independent living skills. Five of the seven students also had a diagnosis of mental retardation. One group (three first graders) was taught the tasks of folding a shirt, making an emergency telephone call, and spreading soft foods with a knife. The other group (four young men) was taught to increase leisure skills through three different leatherwork tasks. Independence training was conducted in a group format, and included social learning components (e.g., self-evaluation, peer evaluation and reinforcement) in addition to traditional operant procedures (e.g., modeling, prompting). However, due to the presence …

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The Effect Of Threecornered Alfalfa Hopper Populations On Alfalfa Growth And The Development Of Host Plant Resistance Screening Techniques., Daniel John Moellenbeck Jan 1992

The Effect Of Threecornered Alfalfa Hopper Populations On Alfalfa Growth And The Development Of Host Plant Resistance Screening Techniques., Daniel John Moellenbeck

LSU Historical Dissertations and Theses

This dissertation research was designed with three main objectives: to evaluate the effects of threecornered alfalfa hopper, Spissistilus festinus (Say), feeding on alfalfa, Medicago sativa L., yield, regrowth, root carbohydrate composition, and disease incidence; to screen alfalfa cultivars for resistance to the threecornered alfalfa hopper and develop effective screening techniques; and to determine the mechanism(s) of this resistance. Greenhouse studies determined the effects of threecornered alfalfa hopper infestations on alfalfa growth and their relationship with Fusarium crown-rot. Significant interaction effects between insect population and the presence of Fusarium were found for number of harvestable stems and acid detergent fiber concentration. …

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A Comparison Of Language And Graphic Products Of Students From Kindergarten Classrooms Differing In Developmental Appropriateness Of Instruction., Jean Germany Mosley Jan 1992

A Comparison Of Language And Graphic Products Of Students From Kindergarten Classrooms Differing In Developmental Appropriateness Of Instruction., Jean Germany Mosley

LSU Historical Dissertations and Theses

This study examines the ways in which kindergartners from more and less developmentally appropriate classrooms negotiate the process of graphic communication. Both quantitative and qualitative aspects of this process are examined. Eighty-one kindergarten children from four classrooms were asked to tell a story both verbally and graphically. They were encouraged to include drawing, writing, or both on their paper. Then they were asked to tell the story that they had produced graphically. The children were students in one of four classrooms from a single school system that were identified as: (a) most developmentally appropriate beliefs and practices; (b) developmentally appropriate …

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Integrated Pest Management Studies Of The Cotton Aphid, Aphis Gossypii Glover., Patti Jane O'Brien Jan 1992

Integrated Pest Management Studies Of The Cotton Aphid, Aphis Gossypii Glover., Patti Jane O'Brien

LSU Historical Dissertations and Theses

Studies were conducted to characterize insecticide resistance and to document aspects of the basic biology of the cotton aphid, Aphis gossypii Glover, that were related to recommendations for integrated pest management. Laboratory, greenhouse, and field techniques were employed in these investigations. Significant levels of resistance were demonstrated to four recommended insecticide classes. Resistance appeared more stable over time for the organophosphate insecticide (chlorpyrifos) than for the organochlorine (endosulfan) and pyrethroid (bifenthrin) insecticide tested. The organophosphate resistance ratio of a clonal line of the cotton aphid was significant, but relatively low. Carboxylesterases, as studied by spectrophotometric and electrophoretic techniques, appeared involved …

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Leader-Member Exchange Quality: The Relationship Of Similarity, Competence, And Selected Personality Variables., Antoinette S. Phillips Jan 1992

Leader-Member Exchange Quality: The Relationship Of Similarity, Competence, And Selected Personality Variables., Antoinette S. Phillips

LSU Historical Dissertations and Theses

The Leader-Member Exchange (LMX) model (e.g., Cashman, Dansereau, Graen, & Haga, 1976; Dansereau, Cashman, & Graen, 1973) contends that leaders react differently with individual followers, rather than treating them homogeneously. Specifically, it assumes that leader behavior depends on relationships with individual work unit members. It further contends that followers vary in their perceptions of and reactions to leader behaviors. Followers, based on their interpersonal relationships (exchanges) with a leader, tend to form two qualitatively different groups, an in-group (higher quality) and an out-group (lower quality). Previous research has documented that insiders and outsiders may experience very different work outcomes. Factors …

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Analysis Of Protein Factors Involved In Transport Of The Precursor Of The Small Subunit Of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase Into Intact Chloroplasts., Steven Mark Pomarico Jan 1992

Analysis Of Protein Factors Involved In Transport Of The Precursor Of The Small Subunit Of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase Into Intact Chloroplasts., Steven Mark Pomarico

LSU Historical Dissertations and Theses

Two protein factors involved in the transport of precursor proteins into intact chloroplasts have been examined. The first of these was observed in experiments utilizing fusion proteins containing various lengths of wheat pS fused to CaM. Transport experiments with these fusion proteins demonstrated a requirement for transport of a pS/CaM fusion protein of a portion of mature S greater than 4 amino acids. Additionally, when the CaM portion of a fusion protein adopted a stable conformation by binding Ca$\sp{2+}$, a larger portion of mature S was needed for efficient transport. A second protein factor was examined using DIDS, and the …

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Quality Enhancement Through Goal-Setting: Examining The Effects Of Goal Attributes And Feedback On Performance., Paula Lynne Phillips Jan 1992

Quality Enhancement Through Goal-Setting: Examining The Effects Of Goal Attributes And Feedback On Performance., Paula Lynne Phillips

LSU Historical Dissertations and Theses

A laboratory experiment, using 165 students, was conducted to assess the effects of goal type (quantity vs quality), goal difficulty (difficult vs easy), goal specificity (specific vs nonspecific), and feedback type (goal-discrepant vs strategic) on performance. Subjects were asked to perform a heuristic task, appropriate for the assessment of both quantity and quality performance. Results indicated: (a) the provision of quality feedback will increase effort and will improve quality performance; (b) individuals value quality feedback more than they value quantity feedback; (c) individuals are more accurate in their prediction of quantity performance than they are in their prediction of quality …

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Effects Of Job Applicant Past Performance And Interpersonal Attraction On Evaluator Attributions And Selection Decisions., Carl R. Phillips Jan 1992

Effects Of Job Applicant Past Performance And Interpersonal Attraction On Evaluator Attributions And Selection Decisions., Carl R. Phillips

LSU Historical Dissertations and Theses

The purpose of the present study was to examine the main and interactive effects of applicant past performance and interpersonal attraction on evaluator attributions and selection decisions; and the effects of evaluator attributions on selection decisions. One hundred seventy-two male and female students enrolled in undergraduate principles of management classes participated in the study. Subjects evaluated an application for an on-campus position and were asked to make selection decisions (i.e., rating applicant's chances of being selected for an interview and eventually receiving a job offer). The results indicated a main effect of applicant past performance (educational and work-related) on selection …

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Physiology And Biochemistry Of A Lignin-Degrading Bacterium Erwinia Sp. Cu 3614., Janardhanan S. Rajan Jan 1992

Physiology And Biochemistry Of A Lignin-Degrading Bacterium Erwinia Sp. Cu 3614., Janardhanan S. Rajan

LSU Historical Dissertations and Theses

Previous researchers have reported the isolation of a diphenylether cleaving organism, Erwinia sp., using an enrichment medium containing lignin. A copper and dinitrophenol resistant mutant of this organism, Erwinia sp. Cu3614, has also been reported. To assess the effect of copper on the growth and biochemistry of this organism, continuous cultivation was used employing an apparently optimized medium containing ethanol as carbon source. Upon increasing the concentration of copper sulfate in the medium from 5 $\mu$g/ml to 10 $\mu$g/ml increases in maximum specific growth rate and growth yield were seen. Also decrease in the values for doubling time and the …

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A Multi-Criterion Transactional Model., Bradley Shawn O'Hara Jan 1992

A Multi-Criterion Transactional Model., Bradley Shawn O'Hara

LSU Historical Dissertations and Theses

This objectives of this dissertation were: (1) to conceptualize and test the influence of transactional elements, personal elements, and contextual elements on the transactional outcomes of trust, satisfaction and commitment; (2) to examine the role of external variables on transactional outcomes; and (3) to assess the interaction among transactional outcomes. Two hundred and eighteen propane gas retailers completed a mail questionnaire concerning an interaction (either discrete or on-going) with one of their suppliers. Perceptions around norms of the contract with this supplier (i.e., solidarity, role integrity), personal characteristics and traits of the salesperson (i.e., similarity, expertise, ethical orientation, customer orientation), …

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A Regional Market Model For Construction Aggregate Materials., Alicia Norma Rambaldi Jan 1992

A Regional Market Model For Construction Aggregate Materials., Alicia Norma Rambaldi

LSU Historical Dissertations and Theses

The primary objective of this dissertation is to model the regional markets for traditional construction aggregates, sand, gravel, and crushed stone. The long-term dynamics of the construction industry related to the demand for aggregates is modeled through a partial adjustment mechanism. The dynamics of the construction industry is introduced into the estimation of a simultaneous equations model of the demand and supply for aggregates at district levels. An engineering-based cost function for extraction of sand and gravel is estimated based on data collected from an operator's survey in the states of Alabama, Arkansas, Louisiana, Mississippi, and Texas. A step-supply for …

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Perceptual Evaluation Of Infant Articulatory Transitions., Nancye Chaney Roussel Jan 1992

Perceptual Evaluation Of Infant Articulatory Transitions., Nancye Chaney Roussel

LSU Historical Dissertations and Theses

The transition portion of the speech signal has been identified as critical to the perception of both consonants and vowels. Furui (1986) demonstrated that for adult Japanese speakers a 10 ms segment of the transition centered on the area of maximum spectral movement contained the most critical information for joint consonant and vowel perception. The distribution of phonemic cues contained within consonant-vowel (CV) non-reduplicated (NRB) syllables of infants ages 6 months to 15 months was compared to the distribution observed in adult productions to examine the extent of coproductive overlap of infant consonant and vowel gestures. Truncated versions of infant …

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Predicting Success Of Minority Nursing Students On The "New" Nclex-Rn., Janet Simmons Rami Jan 1992

Predicting Success Of Minority Nursing Students On The "New" Nclex-Rn., Janet Simmons Rami

LSU Historical Dissertations and Theses

The purpose of this study was to identify academic variables that could be used to forecast success for minority, baccalaureate (BSN) students enrolled in higher education in the south. A second purpose was to develop a methodological framework for predicting success on the post-1988 versions of the National Council Licensure Examination for Registered Nurses (NCLEX-RN), that enhanced external validity, and generalizability. The best predictors of success for minority BSN nursing students were the Mosby assesstest, school comprehensive exit exams, GPA microbiology, the college cumulative GPA, nursing course cumulative GPA, and ACT composite. The sample included 216 Black graduates of three …

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Ecosystem Models Of Aquatic Primary Production And Fish Migration In Laguna De Terminos, Mexico., Enrique Reyes Jan 1992

Ecosystem Models Of Aquatic Primary Production And Fish Migration In Laguna De Terminos, Mexico., Enrique Reyes

LSU Historical Dissertations and Theses

Laguna de Terminos is Mexico's largest coastal lagoon. There is a high habitat diversity including open water, mangroves, seagrasses and marshes, which supports Mexico's most economically important fisheries. Understanding ecosystem processes is essential for effective management of the lagoon's resources. This research developed landscape-level models for aquatic primary production (LAPPTER model), and fish migration (ROE model) in Laguna de Terminos. The ROE model was developed first as a theoretical approach, and later integrated into the LAPPTER model as a submodule which utilizes simulated production as a food source. The ROE model includes behavioral rules for fish movement based on environmental …

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The Role Of Orbitofrontal And Temporal Lobe Cortices In Olfactory Memory Function., Robert Mansfield Savage Jan 1992

The Role Of Orbitofrontal And Temporal Lobe Cortices In Olfactory Memory Function., Robert Mansfield Savage

LSU Historical Dissertations and Theses

Temporal lobe cortex was found to be essential to the initial processing of odor information within the cortex. This brain area can recognize previously smelled odors independent of damaged orbitofrontal cortex. In contrast, orbitofrontal cortex was found to be essential to identifying odors and attaching a verbal or nonverbal label to odor stimuli. These findings were observed in three brain-damaged groups, those with left hemisphere stroke (CVA), right hemisphere CVA, and traumatic brain injury (TBI). The differential pattern of performance observed for CVA and TBI subjects on odor identification and odor recognition tasks suggests that temporal lobe and orbitofrontal olfactory …

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Developing A Research Agenda For The Louisiana Cooperative Extension Service., Fred S. Sanders Jr Jan 1992

Developing A Research Agenda For The Louisiana Cooperative Extension Service., Fred S. Sanders Jr

LSU Historical Dissertations and Theses

The primary purpose of this study was to determine potential future research priorities for the Louisiana Cooperative Extension Service. The Delphi method of forecasting was determined to be the most appropriate for use in this study. Having a knowledge of, and a current relationship with, the Louisiana Cooperative Extension Service (LCES) was the initial criteria for selecting panelists for this study. The final panel consisted of forty LCES personnel. Three rounds of questionnaires were used in this study. The Round 0 questionnaire was open-ended and was used to generate a list of perceived research items most in need of research …

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The Effects Of Prompting On Catching Proficiency Of Young Mildly Retarded Children., Joseph G. Schmalfeldt Jan 1992

The Effects Of Prompting On Catching Proficiency Of Young Mildly Retarded Children., Joseph G. Schmalfeldt

LSU Historical Dissertations and Theses

This study sought to determine the effects of prompting on the catching proficiency of young mildly mentally retarded boys. The study randomly assigned seventy-two 7 year old boys, thirty-six nondisabled and thirty-six mildly mentally retarded, to 3 treatment groups. The treatment were No, 1 or 3 prompts. The subjects were initially given an catching proficiency pretest. Next, they were given 6 practice sessions over a 2 week period. Finally, they were given a catching proficiency posttest. Both the mentally retarded and nondisabled groups in this study improved with practice. In terms of prompting, 1 prompt was as effective as 3 …

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The Effect Of Instructional Videos And Simulation-Gaming Activities In The Environmental Science Curriculum On Knowledge And Attitudes., Lyle Mark Soniat Jan 1992

The Effect Of Instructional Videos And Simulation-Gaming Activities In The Environmental Science Curriculum On Knowledge And Attitudes., Lyle Mark Soniat

LSU Historical Dissertations and Theses

As a result of science reform efforts in the United States numerous shortcomings of the predominant curricula have been identified. The following study evaluates a modular, environmental science curriculum entitled Wild Louisiana, which attempts to address these shortcomings. Wild Louisiana is Science-Technology-Society (STS) oriented and infuses regionally based instructional videos and simulation-gaming activities into the secondary science curriculum. The videos and activities depict the confluence of regional biological, technical, and social phenomena to illustrate universal environmental concepts. The multimedia, modular approach is intended to address the varied learning styles of different students. Following random selection, teachers were randomly assigned to …

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Predicting Kindergarten Success: Use Of The Lens Model Methodology To Determine Factors Which Predict Success In The Kindergarten Classroom., Karen Lynne Serrett Jan 1992

Predicting Kindergarten Success: Use Of The Lens Model Methodology To Determine Factors Which Predict Success In The Kindergarten Classroom., Karen Lynne Serrett

LSU Historical Dissertations and Theses

Recent developments, including and especially the passage of legislation such as P.L. 99-457, have led to a call for more sophisticated technology to accurately assess at-risk preschool children. In addition, there is an urgent need for well trained professionals to perform these assignments. The purpose of the present study was to utilize the Lens Model methodology to examine variables professionals believe are important predictors of successful kindergarten functioning. In addition, the study also explored which variables would actually predict successful kindergarten functioning. Four major findings emerged from the study. First, results indicated that, for the professionals, Social Skills and Cognitive …

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Organic-Rich Lower Tertiary Shales, South Louisiana: Implications For Petroleum Source Rock Deposition., Elizabeth Wyatt Chinn Mcdade Jan 1992

Organic-Rich Lower Tertiary Shales, South Louisiana: Implications For Petroleum Source Rock Deposition., Elizabeth Wyatt Chinn Mcdade

LSU Historical Dissertations and Theses

This study presents comprehensive organic geochemical evidence of organic-rich marine shales in the middle Eocene lower part of the Claiborne Group and the lower Eocene-Paleocene Wilcox Group of south Louisiana. The shales are the only post-Cretaceous age sediments in the northwest Gulf of Mexico basin that fit the conventional criteria for liquid hydrocarbon source rocks. Visual and geochemical evidence suggests that the Paleogene shales contain terrestrially derived, amorphous kerogen with high hydrogen indices whose oil potential has been upgraded by bacterial degradation. The Paleogene section is at immature to late mature levels with respect to petroleum generation, at present-day burial …

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Three-Dimensional Nonlinear Analysis Of Components Of Reinforced Concrete Framed Structures., Srinivas Maddipudi Jan 1992

Three-Dimensional Nonlinear Analysis Of Components Of Reinforced Concrete Framed Structures., Srinivas Maddipudi

LSU Historical Dissertations and Theses

This study deals with the three dimensional analysis of reinforced concrete structural members under multiaxial loading conditions. An incremental formulation in conjunction with the finite element method is used to simulate the behavior of reinforced concrete material. A hypoelastic model capable of simulating response of plain concrete under nonproportional loading conditions is employed. A five parameter strength envelope is used to predict the failure of concrete in multiaxial stress states. A smeared crack model capable of handling multiple non-orthogonal cracks is used to represent the post cracking behavior of concrete. Objectivity in the results of analysis utilizing the smeared cracking …

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Effect Of Soil Redox Potential Andph On Nutrient Uptake By Rice With Special Reference To Arsenic Forms And Uptake., Alfredo Ruben Marin Jan 1992

Effect Of Soil Redox Potential Andph On Nutrient Uptake By Rice With Special Reference To Arsenic Forms And Uptake., Alfredo Ruben Marin

LSU Historical Dissertations and Theses

Studies dealing with the availability and speciation of arsenic (As) as affected by soil redox potential and pH were initiated because of the lack of information on As chemistry in flooded soils. The chemistry of native and applied As was studied in a Crowley silt loam soil (Typic Albaqualf). Arsenic uptake and its toxic effect on two rice cultivars as affected by As chemical form and concentration were also studied. Soil redox potential and pH were shown to affect speciation and solubility of both native and applied As. Upon soil reduction, indigenous-As solubility increased, and arsenite (As(III)) comprised most of …

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A Computational Framework For Efficient Error Correcting Codes Using An Artificial Neural Network Paradigm., Maung Maung Htay Jan 1992

A Computational Framework For Efficient Error Correcting Codes Using An Artificial Neural Network Paradigm., Maung Maung Htay

LSU Historical Dissertations and Theses

The quest for an efficient computational approach to neural connectivity problems has undergone a significant evolution in the last few years. The current best systems are far from equaling human performance, especially when a program of instructions is executed sequentially as in a von Neuman computer. On the other hand, neural net models are potential candidates for parallel processing since they explore many competing hypotheses simultaneously using massively parallel nets composed of many computational elements connected by links with variable weights. Thus, the application of modeling of a neural network must be complemented by deep insight into how to embed …

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Isolation And Oxidative Modifications Of Sesquiterpene Lactones., Isabel Salkeld Nunez Jan 1992

Isolation And Oxidative Modifications Of Sesquiterpene Lactones., Isabel Salkeld Nunez

LSU Historical Dissertations and Theses

In a biochemical systematic study of the tribe Heliantheae, the isolation and structural elucidation of secondary metabolites from four species is reported. The aerial parts of Melampodium leucanthum afforded, besides the known melampolides melampodin A acetate, leucanthin B and leucanthinin, the new lactone leucanthinin-4-epoxide. Peracid oxidation of leucanthinin provided its monoepoxide derivative, the physical and spectroscopical data of which were identical with the new natural lactone. The isolation and structural elucidation of 7$\alpha$-hydroxydehydrocostus lactone, 13-hydroxy-11,13-dihydro-7,11-dehydro-3-desoxy-zaluzanin C and reynosin from Podachaenium eminens is reported. The isolation of the furanoheliangolides atripliciolide 2-methylbutyrate, atripliciolide tiglate and 17,18-dihydrobudlein A from Pappobolus nigrescens was accomplished. …

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Assimilation Of Organic Contaminants In Wetlands: Processes And A Conceptual Model., John Howard Pardue Jan 1992

Assimilation Of Organic Contaminants In Wetlands: Processes And A Conceptual Model., John Howard Pardue

LSU Historical Dissertations and Theses

Laboratory studies and field measurements were conducted to quantify assimilative capacity of toxic organic contaminants in freshwater wetlands. Studies were conducted for hexachlorobenzene and naphthalene in a mineral-dominated bottomland hardwood forest and an organic matter-dominated freshwater marsh. In laboratory studies, sorption of hexachlorobenzene (HCB) in wetland soil and floodwater was strongly influenced by high levels of naturally occurring dissolved organic carbon (DOC). Organic matter-dominated wetlands (e.g., marshes) demonstrated no advantage over mineral-dominated wetlands (e.g., bottomland hardwood forests) for sorption of HCB due to partitioning in this DOC phase. Over the short-term, sorption of HCB was adequately described using a three-phase …

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