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LSU Historical Dissertations and Theses

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A Rock-Plant Filter Bench-Scale Study And Computer Model., Donna Gail Skipper Jan 1990

A Rock-Plant Filter Bench-Scale Study And Computer Model., Donna Gail Skipper

LSU Historical Dissertations and Theses

In Part One, three bench-scale rock filters containing 2 feet of gravel were investigated. Two of the filters were planted with Sagittaria lancifolia and Scirpus validus, while the third filter was an unvegetated control filter. During a preliminary portion of this study, the BOD$\sb5$ surface loading was held constant at 4.96 g/day/m$\sp2$. The BOD$\sb5$ mass removal percentages at this time averaged 75%, 60%, and 44% for the Scirpus, Sagittaria, and control systems, respectively. Following this constant loading rate, an 80-day experiment was run on the filters using eight combinations of two flow rates and four influent BOD$\sb5$ concentrations, each combination …

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An Investigation Of The Effect Of A Favorable External Quality Assurance Review On The Scope Of The External Auditor's Examination Of An Organization's Financial Statements., Michael Charles Toerner Jan 1990

An Investigation Of The Effect Of A Favorable External Quality Assurance Review On The Scope Of The External Auditor's Examination Of An Organization's Financial Statements., Michael Charles Toerner

LSU Historical Dissertations and Theses

The review team that performs an external quality assurance review of an organization's internal audit department examines factors that are very similar to those considered by the external auditor as part of the evaluation of the department. The purpose of the study was to explore the possibility that an external auditor would modify the scope of the audit work when an organization's internal audit department had received a favorable external quality assurance review. In addition, the study investigated the effect that the type of reviewer who performs an external review has on the scope of the external auditor's work. Data …

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The Social Integration-Deviance Hypothesis In Sociology: The Case Of Teenage Fertility., Stephen Joseph Caldas Jan 1990

The Social Integration-Deviance Hypothesis In Sociology: The Case Of Teenage Fertility., Stephen Joseph Caldas

LSU Historical Dissertations and Theses

The purpose of this dissertation is to construct and test an elaborated version of the social integration-deviance model. Social integration theory traces its origins to Emile Durkheim, who postulated the existence of two forms of social integration, today known as normative and functional integration. In his classic work Suicide (1897/1951) Durkheim first empirically tested his theory of social integration, though arguably only for normative integration. Others have since elaborated on his theory, and have tested various versions of it (Hirschi, 1969; Collette, Webb, & Smith, 1979). The current work conceptualizes teenage childbearing in the United States as deviancy from an …

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A Study Of Nursing Orientation In Two Urban Hospitals. (Volumes I And Ii)., Myrna Harris Cassimere Jan 1990

A Study Of Nursing Orientation In Two Urban Hospitals. (Volumes I And Ii)., Myrna Harris Cassimere

LSU Historical Dissertations and Theses

This case study described the perceptions of participants during an orientation program in two urban hospitals. The conceptual framework of the study is based on the social systems theory of administration by Getzels and Guba (1957). Four propositions were used to guide interviews and observations for data collection. Data analysis was accomplished by the pattern matching technique described by Yin (1984). The study propositions were supported by the data. The participants of the study included new graduates and experienced nurses. The institutions involved and their orientation programs were perceived in a positive manner by the participants. Orientation instructors were perceived …

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Ecology Of Erwinia Chrysanthemi, Causal Agent Of Bacterial Stem And Root Rot On Sweet Potato And Etiology Of Souring., Valmir Duarte Jan 1990

Ecology Of Erwinia Chrysanthemi, Causal Agent Of Bacterial Stem And Root Rot On Sweet Potato And Etiology Of Souring., Valmir Duarte

LSU Historical Dissertations and Theses

During three seasons, mother storage roots of Beauregard sweetpotato were inoculated with Erwinia chrysanthemi in March, and the pathogen was recovered from them the day they were bedded, 7 days later, and at the first and second pullings of slips as well as from underground stems at harvest in September and October of the first and second transplantings, respectively. Little stem rot occurred in the fields during the three seasons. Thirteen strains of E. chrysanthemi, 8 isolated originally from sweetpotato and 5 from other hosts, and one strain of E. carotovora subsp. carotovora were inoculated on sweetpotato and 12 different …

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Design Of A Two-Stage Procedure For Three-Class Screening., Chungtae Kim Jan 1990

Design Of A Two-Stage Procedure For Three-Class Screening., Chungtae Kim

LSU Historical Dissertations and Theses

A two-stage screening procedure is developed for a situation where the items can be sold in one of two markets, or scrapped. The item's selling price and product specifications differ for each market. In the first stage of the screening procedure, each item is inspected on a surrogate variable that is correlated with the performance variable of interest. If a decision is not reached at this point, the item is subjected to a second-stage inspection on a performance variable. A loss in selling price is incurred by the producer when an item that meets the specifications of a higher-price market …

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Biased Estimation In The Context Of The Hedonic Pricing Model For Housing., John Ross Knight Jan 1990

Biased Estimation In The Context Of The Hedonic Pricing Model For Housing., John Ross Knight

LSU Historical Dissertations and Theses

This dissertation compares eight biased estimators as alternatives to Ordinary Least Squares estimation in the context of predicting residential real estate prices. It considers ridge rule estimation and principal components regressions, techniques that have previously been proposed for this application. It also introduces the use of Stein-like rules for predicting housing prices. The study examines relative performance of these estimators in three data settings and under four separate assumptions regarding loss criteria. The first test of the estimators uses Multiple Listing Service (MLS) data for Baton Rouge, Louisiana between 1984 and 1989 to examine relative predictive effectiveness in a time …

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Neutral Impurity Scattering In Semiconductors., Kwok Chuen Kwong Jan 1990

Neutral Impurity Scattering In Semiconductors., Kwok Chuen Kwong

LSU Historical Dissertations and Theses

Neutral impurity scattering is a relatively untouched subject because it is only significant at very low temperatures. With the development of a new class of impurity band conduction devices that operate at cryogenic temperatures, it becomes necessary to describe the scattering in a more realistic fashion. We have calculated both elastic and inelastic scattering of electrons by substitional As in n-type Si, taking into account the anisotropy of the host band structure. Specifically, in regard to inelastic scattering, we calculated the differential and integrated cross sections for transitions from the ground state to the valley-orbit split states $\Gamma\sb{15}$ and $\Gamma\sb{12}$. …

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The Synthesis, Characterization, And Reactivities Of Metal Tetratertiaryphosphine Complexes., Scott Anthony Laneman Jan 1990

The Synthesis, Characterization, And Reactivities Of Metal Tetratertiaryphosphine Complexes., Scott Anthony Laneman

LSU Historical Dissertations and Theses

The synthesis of the binucleating tetratertiary phosphine ligand R$\sb2$PCH$\sb2$CH$\sb2$ (Ph)PCH$\sb2$P(Ph)CH$\sb2$CH$\sb2$PR$\sb2$ (R = Et, Ph), (LTTP), is described and several new bimetallic systems have been characterized. LTTP ligand design features include the combination of bis(phosphino)methane bridge with bis(phosphino)ethane chelating units. These merging functionalities can coordinate two transition metal centers and allow bimetallic reactivity from intramolecular interactions. eLTTP (R = Et) contains electron-rich alkyl-phosphines which also strongly coordinate and discourage fragmentation of the metal complex. Another class of tetratertiaryphosphines, where the central methylene groups is replaced by a central propylene (eLTTP-pr) and/or p-xylylene group (eLTTP-p-xyl), are synthesized and characterized along with three …

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Measurement Of Positron-Electron Going To Baryon-Antibaryon Forward-Backward Charge Asymmetry., Jit Ning Lim Jan 1990

Measurement Of Positron-Electron Going To Baryon-Antibaryon Forward-Backward Charge Asymmetry., Jit Ning Lim

LSU Historical Dissertations and Theses

This dissertation describes the measurement of the forward-backward charge asymmetry, A$\sb{\rm b}$, for e$\sp{+}$e$\sp{-} \to$ bb at TRISTAN by the AMY detector. A measurement of the ratio, R$\sb{\rm b}$, of the cross section for e$\sp{+}$e$\sp{-} \to$ bb to the theoretical QED cross section for e$\sp{+}$e$\sp{-}\ \to\ \mu\sp{+}\mu\sp{-}$ is also obtained. A$\sb{\rm b}$ is an effect of the weak-electromagnetic interference. The measurement of A$\sb{\rm b}$ is therefore a direct test of the standard model electroweak theory. TRISTAN is the only e$\sp{+}$e$\sp{-}$ collider in the world to explore the center-of-mass energy region of 50 GeV to 62 GeV, where the effects of …

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The Effect Of Olivocochlear Bundle Transection On Cochlear Mechanics., Thomas Allen Littman Jan 1990

The Effect Of Olivocochlear Bundle Transection On Cochlear Mechanics., Thomas Allen Littman

LSU Historical Dissertations and Theses

A growing body of research suggests that the efferent innervation to the cochlea, the olivocochlear bundle, plays a role in modulating the mechanical function of the cochlea. Some of the more provocative findings supporting an hypothesis of OCB modulation have come from studies which assessed efferent influences on tuning curves and acoustic distortion products, two measures thought to be sensitive indicators of cochlear mechanical function. While the OCB appears to be capable of modifying cochlear mechanics, the functional role attributed to the efferents has been difficult to define. For example, some studies which have transected all or part of the …

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An Exploration Of The "Paradoxical" View Of Coupling Structure And School Effectiveness., Connie Stokes Logan Jan 1990

An Exploration Of The "Paradoxical" View Of Coupling Structure And School Effectiveness., Connie Stokes Logan

LSU Historical Dissertations and Theses

The purpose of this study was to utilize the organizational perspective of coupling to extend our understanding of effective schools as complex social systems. Part One of the study focused on the continued development and refinement of the Organizational Coupling Structure Inventory-Teacher Form (OCSI-T) to measure coupling structure in schools (Logan & Ellett, 1989). Part Two of the study focused on the examination of key research questions that bear on understanding the coupling construct and school effectiveness. The findings from Part One of the study support the OCSI-T as a reasonably valid and reliable inventory for measuring five dimensions of …

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The Influence Of Prior Performance, Slack, And Top Management Turnover On Divestiture And Subsequent Firm Performance., James Wilburn Logan Jr Jan 1990

The Influence Of Prior Performance, Slack, And Top Management Turnover On Divestiture And Subsequent Firm Performance., James Wilburn Logan Jr

LSU Historical Dissertations and Theses

This research is an investigation of the influence of contextual factors on a multidivisional firm's decision to divest an entire business unit, and the effects of that divestiture on firm operating performance, market performance, and organizational slack generation and usage. Contextual influences and outcomes are assessed for a sample of 102 U.S. based firms representing 43 different industries, as defined by primary four-digit Standard Industry Classification (SIC). This research drew on prior research in strategic management, finance, and organizational theory to develop an integrated model of firm-level influences on divestiture and determine if those influences can be used to predict …

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An Annotated Compendium Of Selected Vocal Solo Literature For Protestant Churches, 1958-1988., David Alan Luther Jan 1990

An Annotated Compendium Of Selected Vocal Solo Literature For Protestant Churches, 1958-1988., David Alan Luther

LSU Historical Dissertations and Theses

The topic of this study is the sacred art song of the past three decades (1958-1988). One-hundred forty-eight songs have been selected for the Compendium which, in the writer's opinion, are suitable in both quality and appropriateness for the Protestant worship service. The listing does not include solo literature which would be classified as "gospel" or "Christian Contemporary," nor does it include selections which may be more fitting for recital use. Each entry gives the title, composer, author of text, publisher, date, range, tessitura, occasion, and type of accompaniment. In the annotation which follows, notable musical and textual features are …

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Molecular Dynamics Of Solutions Containing Water-Soluble Semiflexible Polymer., Mazidah Binti Mustafa Jan 1990

Molecular Dynamics Of Solutions Containing Water-Soluble Semiflexible Polymer., Mazidah Binti Mustafa

LSU Historical Dissertations and Theses

The solution behavior of hydroxypropylcellulose (HPC) was investigated in detail via molecular probe diffusion. The diffusivities of two very different probes, polystyrene latex spheres and sodium fluorescein dye, in aqueous solutions of HPC of three different molecular weights were measured by quasielastic light scattering (QELS) for latex probes and fluorescence photobleaching recovery (FPR) for dye probes. In aqueous HPC, the latex spheres have a tendency to form clusters by adsorption of HPC and bridging of the latex spheres. The microviscosities calculated from the Stokes-Einstein relationship using the bare spheres radii exceeded the measured shear viscosities from cone and plate and …

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Narrative And Everyday Experience: Performance Process In The Storytelling Of The Swiss Volhynian Mennonites. (Volumes I And Ii)., John Elmer Mccabe-Juhnke Jan 1990

Narrative And Everyday Experience: Performance Process In The Storytelling Of The Swiss Volhynian Mennonites. (Volumes I And Ii)., John Elmer Mccabe-Juhnke

LSU Historical Dissertations and Theses

This study examines oral narrative performance within the cultural context of the Swiss Volhynian Mennonites in Moundridge, Kansas, whose forebears were members of a congregational group that migrated from the Russian Province of Volhynia in 1874. These immigrants strove to maintain Gemeinde--a mutually supportive community of believers separated from the world. A Swiss Volhynian Mennonite himself, the author tape-recorded interviews with second and third generation descendants of the Russian immigrants. Using the interview transcriptions and personal observation in the Moundridge community as primary data, the author demonstrates how the formative elements of everyday narrative performance both sustain and are shaped …

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Habitat Use, Movements, And Behavior Of Shiny Cowbirds In Southwestern Puerto Rico., Paul Michael Mckenzie Jan 1990

Habitat Use, Movements, And Behavior Of Shiny Cowbirds In Southwestern Puerto Rico., Paul Michael Mckenzie

LSU Historical Dissertations and Theses

Shiny Cowbirds were primarily located in six major areas of concentration. Of these, all but one was in mesquite woodland. Overall, cowbirds used mesquite woodland almost 75% of the time but use of this habitat varied among weekly periods and was linked to rainfall received during weekly periods prior to the observation. Habitat use of cowbirds and the time they spent eating particular prey items were most correlated with total rainfall received 2-5 weeks prior to the observation (p =.0067 and p =.0149, respectively). Major food items taken by cowbirds following periods of sufficient rainfall were caterpillars, berries and grass …

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Theoretical Orientations Of Chapter I Reading Teachers: Consistency Between Beliefs And Practices., Mary Margaret Mitchell Jan 1990

Theoretical Orientations Of Chapter I Reading Teachers: Consistency Between Beliefs And Practices., Mary Margaret Mitchell

LSU Historical Dissertations and Theses

The purpose of this study was to investigate the consistency between Chapter I teachers' theoretical orientations and instructional practices related to preactive planning and interactive decision-making. Twenty-three Chapter I teachers were administered screening instruments that included: (a) a biographical survey, and (b) instruments focusing on teachers' theoretical orientations about reading and instructional choices. Primary consideration for selection included education and professional experience, beliefs about reading, and instructional decision-making. Based on this information, four Chapter I teachers, each with a reader-based orientation, were purposively selected to participate in this study. For each participant, the researcher selected a pull-out class (6-10 students) …

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Effect Of Acid Rain And Humic Substances On Aluminum Toxicity (And); A Comparative Study Of Chemical Composition Of Old And Newly Deposited Plaque From Heart Patients., Jane Igoki Murungi Jan 1990

Effect Of Acid Rain And Humic Substances On Aluminum Toxicity (And); A Comparative Study Of Chemical Composition Of Old And Newly Deposited Plaque From Heart Patients., Jane Igoki Murungi

LSU Historical Dissertations and Theses

Effect of acid rain and humic acid on aluminum toxicity. A study was carried out to find if leaf extracts could be used to counteract the effect of acid rain and aluminum in soils and lakes. Tilapia, and common shiners fish, and alligator grass plant were used to study the effects of pH and aluminum. The effect of dried leaves on the pH and the buffering capacity of deionized water and the effect of the presence of cations such as iron, calcium and magnesium on aluminum toxicity were investigated. The results of our investigation indicated a synergistic toxic effect of …

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A Monte Carlo Comparison Of Tests For Multivariate Normality Based On Multivariate Skewness And Kurtosis., Ronald Larry Horswell Jan 1990

A Monte Carlo Comparison Of Tests For Multivariate Normality Based On Multivariate Skewness And Kurtosis., Ronald Larry Horswell

LSU Historical Dissertations and Theses

The assumption of multivariate normality (MVN) underlies many common parametric multivariate statistical procedures, and numerous tests have been defined for testing the assumption. Among these tests, those based on concepts of "multivariate skewness" and "multivariate kurtosis" hold special interest since they appear to test for specific types of departures from MVN. This research uses Monte Carlo simulation to compare the performance of several MVN tests which are based on various definitions of multivariate skewness and kurtosis. Specifically, the tests are Mardia's (1970) b$\sb{\rm 1,p}$ and b$\sb{\rm 2,p}$, Small's (1980) Q$\sb1$ and Q$\sb2$, and Srivastava's (1984) b$\sb{\rm 1p}$ and b$\sb{\rm 2p}$. …

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The Geology And Stratigraphic Evolution Of The North-Central Part Of The Early Archean Barberton Greenstone Belt, South Africa., Louise Dorothy Hose Jan 1990

The Geology And Stratigraphic Evolution Of The North-Central Part Of The Early Archean Barberton Greenstone Belt, South Africa., Louise Dorothy Hose

LSU Historical Dissertations and Theses

The north-central part of the 3.5 to 3.2 Ga Barberton greenstone belt, southwest of the town of Barberton, contains both the northern and southern facies of the Swaziland Supergroup including, from base to top, the Onverwacht, Fig Tree, and Moodies Groups. The facies are divided by the Inyoka Fault, a major thrust fault that was reactivated by dextral shearing. The two facies of Fig Tree and Moodies strata appear to be laterally gradational. The Moodies Group, a 2800+ m sequence of predominantly lithic arenite, sublitharenite, and arkosic arenite was studied in four large, structurally isolated blocks in the north-central part …

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Captive-Financing Affiliates, Agency Costs, And The Security Offerings Of Real Estate Investment Trusts., Cheng-Ho Hsieh Jan 1990

Captive-Financing Affiliates, Agency Costs, And The Security Offerings Of Real Estate Investment Trusts., Cheng-Ho Hsieh

LSU Historical Dissertations and Theses

This dissertation explores the agency problems of REITs caused by the conflicts of interest between the REIT sponsor and the REIT shareholders. It also tests the impact of the agency problems on the pricing of REIT initial public offerings (IPOs) and on the valuation effects of secondary debt and equity offerings. Like the IPOs of ordinary corporations, REIT IPOs are also underpriced; however, the magnitude of the underpricing is far lower than that of the IPOs for ordinary corporations. Captive REITs have greater underpricing in IPOs than non-captive REITs. REIT secondary equity offerings exhibit negative announcement effects, while secondary debt …

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The Transport And Fate Of Chromium(Vi) In Deep Well Disposal Zone., Jaehyuk Hyun Jan 1990

The Transport And Fate Of Chromium(Vi) In Deep Well Disposal Zone., Jaehyuk Hyun

LSU Historical Dissertations and Theses

Several parameters affecting the behavior of Chromium(+VI) in deep well injection zones were studied. Temperature, pH, concentration of inorganic salt in wastewater, and organic chemicals co-injected with wastewater were considered as they affect the adsorption and reduction rates of Cr(VI). Water content, bulk density of shale and sand, and temperature were examined for their effect on the diffusion rate of Cr(VI) in porous media. Adsorption and reduction of Cr(VI) were investigated using three clays, Na-Montmorillonite, Illite, and Kaolinite, and sand from an injection well formation in southern Louisiana, and a confining layer shale obtained from a second Louisiana injection well. …

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A Functional Approach To Model Management., Lijen Ko Jan 1990

A Functional Approach To Model Management., Lijen Ko

LSU Historical Dissertations and Theses

A model management system (MMS) is a computer-based system which facilitates the management of a wide range of decision support models (DSMs). It is a vital component of a decision support system which helps decision makers using data and DSMs in an integrated fashion. It is desirable that an MMS is knowledge-based, flexible, independent and reflecting users' view of a DSM. In addition, an MMS must manage DSMs at both the macro and micro levels. At the macro level, DSMs are described using descriptive attributes to supply users with general problem-solving capabilities. At the micro level, the components and mathematical …

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Itchgrass Interference And Control In Sugarcane In Louisiana., Reed John Lencse Jan 1990

Itchgrass Interference And Control In Sugarcane In Louisiana., Reed John Lencse

LSU Historical Dissertations and Theses

The spread of itchgrass (Rottboellia cochinchinensis (Lour.) Clayton) throughout the sugarcane (Saccharum interspecific hybrids) area is of growing concern to producers in Louisiana. At Maringouin and Thilbodaux, LA, season-long itchgrass interference reduced sugarcane stalk populations, cane yields, and sugar yields 34, 42, and 43%, respectively, compared to no itchgrass interference. Stalk populations and cane and sugar yields were comparable for early-season (from spring until layby on June 12) and season-long itchgrass interference with late-season (from layby on June 12 until harvest) being similar to no itchgrass interference. Good to excellent early-season itchgrass control was obtained with pendimethalin at 2.2 and …

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A Rhetorical Analysis Of The Scientific-Romantic Synthesis In The Popular Scientific Writings Of Lewis Thomas., Donald Paul Lee Jan 1990

A Rhetorical Analysis Of The Scientific-Romantic Synthesis In The Popular Scientific Writings Of Lewis Thomas., Donald Paul Lee

LSU Historical Dissertations and Theses

As physician, educator, former medical administrator, and member of the National Academy of Sciences, Lewis Thomas has been one of the most eloquent spokespersons for the scientific community. This dissertation analyzes twenty-four of Thomas' popular scientific essays. These essays reveal a union of traditional scientific values and popular romantic themes, what is called here a rhetorical synthesis. The term synthesis is understood as the putting of two or more things together to form a whole, particularly suggesting a reconciliation of two philosophically opposing forces. Thomas' essays reflect a synthesis insofar as they merge what have traditionally been thought to be …

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Genotypic And Phenotypic Adaptations Of The Southern Oyster Drills, Stramonita Canaliculata And S. Haemastoma Floridana To Salinity., Li-Lian Liu Jan 1990

Genotypic And Phenotypic Adaptations Of The Southern Oyster Drills, Stramonita Canaliculata And S. Haemastoma Floridana To Salinity., Li-Lian Liu

LSU Historical Dissertations and Theses

Environmental and genetic effects on salinity adaptation in the southern oyster drill were estimated by their salinity-related genotypic (i.e. determined by electrophoresis) and phenotypic (i.e. determined by salinity tolerance and microcalorimetry) variations. The systematics of Stramonita haemastoma were studied using allozyme, radular and shell characteristics to exclude taxonomic differences which might have obscured variations in salinity adaptation. Radular and shell features are not reliable as systematic characteristics. S. h. canaliculata and S. h. floridana are separable using allozyme characteristics. Nei's genetic distance (D = 0.28) and the fixed allelic differences in Fum, LeuAla, Mdh, and 6-Pgdh indicate that the differences …

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The Combustion Of Linear Droplet Arrays In A Coaxial Convective Flow., Jeng-Syan Tsai Jan 1990

The Combustion Of Linear Droplet Arrays In A Coaxial Convective Flow., Jeng-Syan Tsai

LSU Historical Dissertations and Theses

As approximations for spray-combustion processes, a series of increasingly sophisticated numerical models has been developed to simulate the combustion of linear droplet arrays in a co-axial, convective flow. Common to all of the models is an embedded grid, developed to increase computational accuracy. The first and simplest model is potential flow model (for Re $\to$ $\infty$). The flow is assumed to be ideal and infinitely-fast kinetics (flame sheet assumption) represent the combustion. The results show that the instantaneous droplet burning rates are increased as the droplet spacing is increased, and the burning rates of droplets tend asymptotically to smaller values …

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Rice Improvement Through Tissue Culture: Inheritance Of Somaclonal Variation And Improvement Of Somaculture Techniques., Qingjun Xie Jan 1990

Rice Improvement Through Tissue Culture: Inheritance Of Somaclonal Variation And Improvement Of Somaculture Techniques., Qingjun Xie

LSU Historical Dissertations and Theses

The objectives of this research were to study the inheritance of homozygous variation from rice somaculture, to select rice somaclones for increased sheath blight resistance, and to determine the mode of inheritance of the resistance. To accomplish these objectives it was necessary to improve somaculture techniques for rice suspension and protoplast culture especially for the American long-grain cultivars. A method for incorporation of the chemical mutagen, ethyl methane-sulfonate (EMS), into the somaculture system was also developed to increase the frequency of somaclonal variation in tissue culture stable cultivars. The inheritance of six homozygous variant characteristics from five somaclones was investigated. …

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A Geographic Information System For Risk Assessment Of Fasciola Hepatica In Cattle., Stanley Harland Zukowski Jan 1990

A Geographic Information System For Risk Assessment Of Fasciola Hepatica In Cattle., Stanley Harland Zukowski

LSU Historical Dissertations and Theses

A geographic information system (GIS) was used to assemble and analyze data on the spatial distribution of habitat of the snail, Fossaria bulimoides, an intermediate hose of Fasciola hepatica. A model of habitat was developed on a single 760ha farm on the Chenier Plain of southwestern Louisiana and extrapolated for testing on 12 other farms in a 29,000ha extended study area of the Chenier Plain region. Input maps were: (1) soil series (type), (2) fencelines, (3) F. bulimoides habitat, and (4) soil salinity. On the primary study farm, habitat was strongly associated with interfaces of marsh and chenier (relict beach) …

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