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Applications Of Solid State Deuterium Nmr Spectroscopy., William Lawrence Jarrett Jr Jan 1988

Applications Of Solid State Deuterium Nmr Spectroscopy., William Lawrence Jarrett Jr

LSU Historical Dissertations and Theses

Solid-state deuterium NMR spectroscopic techniques have been applied to a series of organic and organometallic systems. The construction and operation of an ADLF (adiabatic demagnetization in the laboratory frame) spectrometer is described in detail. The instrument has been used to obtain high-field solid-state deuterium NMR spectra for a series of para-substituted phenyl acetic acids which have been deuteriated at the methylene site, as well as $d\sb1$-napthalene, triphenylphosphonium-(methyl-$d\sb3$) bromide, and barium chlorate monohydrate (25% deuteriated). The data for the para-substituted phenyl acetic acids show that the two methylene deuterons are inequivalent. This inequivalency is due to the difference in the $\sp2$H-C$\sb1$-C$\sb2$-O …

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Entity Relationship Approach To Knowledge Base Systems., Sreerama Krishna Karukonda Jan 1988

Entity Relationship Approach To Knowledge Base Systems., Sreerama Krishna Karukonda

LSU Historical Dissertations and Theses

A unified framework for knowledge base systems is proposed based on Entity-Relationship (ER) approach. Following the analysis and the specification of the real-world using Entity-Relationship approach, the knowledge base is implemented as a first-order logic system, a production system, or a frame-based system by mapping the appropriate symbolic data structures. An approach for analyzing and specifying real-world perceptions must provide appropriate semantic primitives. Therefore, a justification is provided for the semantic primitives proposed in Entity-Relationship approach by considering the fundamental issues in perception. A notation that allows Entity-Relationship approach to be used as a holistic representation is presented. Translation rules …

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The Dextranase Of Lipomyces Starkeyi And Its Use In Sugar Cane Processing., David William Koenig Jan 1988

The Dextranase Of Lipomyces Starkeyi And Its Use In Sugar Cane Processing., David William Koenig

LSU Historical Dissertations and Theses

Dextranase is an enzyme which destroys dextran, a contaminant in sugar and a main constituent of dental plaque. Dextranase utilization can solve a major economic problem in the sugar industry, and in dental preparations it can keep teeth essentially free of plaque. The dextranase from the yeast Lipomyces starkeyi was investigated because this organism has been used in food related processes. This attribute should allow for Food and Drug Administration (FDA) approval for use of a Lipomyces dextranase. None of the existing commercial dextranase preparations have FDA approval. L. starkeyi was found to produce maximum amounts of dextranase when grown …

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The Role Of Curved Dna In Promoter Selection By The Major Bacillus Subtilis Rna Polymerase., Carl Feemster Mcallister Jan 1988

The Role Of Curved Dna In Promoter Selection By The Major Bacillus Subtilis Rna Polymerase., Carl Feemster Mcallister

LSU Historical Dissertations and Theses

The major RNA polymerases of Bacillus subtilis and Escherichia coli recognize the same conserved sequences at $-$10 and $-$35 of the promoter. The B. subtilis enzyme requires additional DNA sequences for efficient promoter utilization. Deletion mutants were used to demonstrate that the function of two B. subtilis phage SP82 promoters, Ba1129 and Alu156, was dramatically affected by sequence upstream from $-$35. The upstream DNA contained runs of four to six adenines with a 10-11 base pair periodicity. Indicative of DNA curvature, these regions decreased electrophoretic mobility of DNA fragments containing either promoter. The curved upstream DNA increased the affinity of …

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The Relative Effects Of Salespersons' Ratings On Ability And Effort Criteria., Sandra Edwards Mckay Jan 1988

The Relative Effects Of Salespersons' Ratings On Ability And Effort Criteria., Sandra Edwards Mckay

LSU Historical Dissertations and Theses

Performance appraisal is a crucial function of sales managers. Often, performance appraisal information is used as a basis for decisions relating to pay, promotion, and termination. Such decisions can have a substantial impact on the motivation, satisfaction, and productivity of members of the sales force. Despite its importance, little research has investigated the way in which decisions concerning salesperson performance are made. The primary goal of this research was to examine the relative effects of salespeople's ability and effort on decisions relating to promotion, compensation, transfer, and termination. A secondary purpose was to see if salesperson sex influenced these decisions. …

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Genetics Of Resistance To Reniform Nematode, Rotylenchulus Reniformis Linford And Oliveira, In Cotton, Gossypium Hirsutum L., Noor Muhammad Jan 1988

Genetics Of Resistance To Reniform Nematode, Rotylenchulus Reniformis Linford And Oliveira, In Cotton, Gossypium Hirsutum L., Noor Muhammad

LSU Historical Dissertations and Theses

Four Gossypium hirsutum L. lines (La. RN 910, Auburn 612 RNR, M 019-RNR, and 'Deltapine 41' (Dp 41)) were selected for a genetic study of their reaction to reniform nematode, Rotylenchulus reniformis Linford and Oliveira, based on observed differences. Dp 41 (susceptible) was crossed to each of the three moderately resistant lines. F$\sb1$ generations were selfed and each was backcrossed to each of its parents. Estimates of mean gene effects and the three types of digenic epistatic effects affecting genetic variation of resistance to reniform were calculated using the generation means of P$\sb1$, P$\sb2$, F$\sb1$, F$\sb2$, P$\sb1$F$\sb1$, and P$\sb2$F$\sb1$. Six …

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Study On The Translation Initiation Mechanism On Picornaviral Rna., In-Woo Park Jan 1988

Study On The Translation Initiation Mechanism On Picornaviral Rna., In-Woo Park

LSU Historical Dissertations and Theses

To understand the initiation of translation of picornavirus RNA, cell-free translation of the RNA of encephalomyocarditis virus (EMCV) was examined after hybridization of chemically synthesized cDNA fragments to different sites of the 5$\sp\prime$ untranslated region (5$\sp\prime$ UTR) of the viral RNA and after deletion of specific segments of the 5$\sp\prime$ UTR by RNase H digestion. In addition, "translation competition" experiments, using RNA fragments derived from different parts of the 5$\sp\prime$ UTR, were performed. The results of these experiments are summarized as follows: (i) Binding of cDNA fragments to sequences between the 5$\sp\prime$ terminus and nucleotide 338 caused no effect on …

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Thinking Processes, Management Routines And Student Perceptions Of Expert And Novice Physical Education Teachers., Karyn R. Nelson Jan 1988

Thinking Processes, Management Routines And Student Perceptions Of Expert And Novice Physical Education Teachers., Karyn R. Nelson

LSU Historical Dissertations and Theses

This study examined thought processes including problem-solving and interpretations of instructional situations of expert and novice physical education teachers at two grade levels. Four expert and four novice teachers (two each at the third grade and two each at the seventh grade) participated in the study. Thoughts, concerns, decisions, and awarenesses of expert and novice teachers during instruction were evaluated as well as their students' perceptions of the instruction. A total of 144 students were interviewed. Class rules and management routines established during the first week of the school year by two of the expert teachers (one at each grade …

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Soil Sorption And Plant Uptake Of 2,4,6-Trinitrotoluene., Judith Carol Pennington Jan 1988

Soil Sorption And Plant Uptake Of 2,4,6-Trinitrotoluene., Judith Carol Pennington

LSU Historical Dissertations and Theses

Potential environmental hazards are posed by the presence of 2,4,6-Trinitrotoluene (TNT) contamination in soils of US Army Ammunition Plants (AAPs). Adsorption and desorption studies were conducted on soil samples collected from 13 AAPs. Soils were found to be primarily silt loams, low in organic carbon. TNT reached a steady state of adsorption with test soils within 2 hrs of contact. Desorption also reached steady state within 2 hrs with more than half of the adsorbed TNT being removed. Batch adsorption isotherms were best fit by the Langmuir adsorption model. Average adsorption coefficients (soil concentration to solution concentration), or K$\sb{\rm d}$, …

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An Algorithmic Framework For Robot Navigation In Unknown Terrains., Nageswara S. V Rao Jan 1988

An Algorithmic Framework For Robot Navigation In Unknown Terrains., Nageswara S. V Rao

LSU Historical Dissertations and Theses

The problem of navigating a robot body through a terrain whose model is a priori known is well-solved problem in many cases. Comparatively, a lesser number of research results have been reported about the navigation problem in unknown terrains i.e., the terrains whose model are not a priori known. The focus of our work is to obtain an algorithmic framework that yields algorithms to solve certain navigational problems in unknown terrains. We consider a finite-sized two-dimensional terrain populated by a finite set of obstacles $O$ = $\{O\sb1,O\sb2,\...,O\sb{n}\}$ where $O\sb{i}$ is a simple polygon with a finite number of vertices. Consider …

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A Study To Investigate The Effects Of State Taxation And Plan Type On Small Employer Retirement Plan Cost., W. Robert Smith Jan 1988

A Study To Investigate The Effects Of State Taxation And Plan Type On Small Employer Retirement Plan Cost., W. Robert Smith

LSU Historical Dissertations and Theses

Congress enacted legislation in 1978 (Revenue Act of 1978) that created a new type of retirement plan, the simplified employee plan. Congress believed that the administration costs associated with existing plans, especially qualified plans, were an undesirable obstacle to plan adoption and maintenance among small employers. Qualified plan participants, i.e., employees, in many cases are able to receive substantial reductions in the amount of tax due on retirement plan distributions. One of the primary differences between qualified plans and the simplified employee plans mentioned above is that under certain circumstances the tax due on distributions from qualified plans may be …

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Intensional Query Processing In Deductive Database Systems., Il Yeol Song Jan 1988

Intensional Query Processing In Deductive Database Systems., Il Yeol Song

LSU Historical Dissertations and Theses

This dissertation addresses the problem of deriving a set of non-ground first-order logic formulas (intensional answers), as an answer set to a given query, rather than a set of facts (extensional answers), in deductive database (DDB) systems based on non-recursive Horn clauses. A strategy in previous work in this area is to use resolution to derive intensional answers. It leaves however, several important problems. Some of them are: no specific resolution strategy is given; no specific methodologies to formalize the meaningful intensional answers are given; no solution is given to handle large facts in extensional databases (EDB); and no strategy …

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Neural Networks With Asynchronous Control., Michael Christopher Stinson Jan 1988

Neural Networks With Asynchronous Control., Michael Christopher Stinson

LSU Historical Dissertations and Theses

Neural network studies have previously focused on monolithic structures. The brain has a bicameral nature, however, and so it is natural to expect that bicameral structures will perform better. This dissertation offers an approach to the development of such bicameral structures. The companion neural structure takes advantage of the global and subset characteristics of the stored memories. Specifically we propose the use of an asynchronous controller C that implies the following update of a probe vector x by the connection matrix T: $x\sp\prime$ = sgn (C(x, TX)). For a VLSI-implemented neural network the controller block can be easily placed in …

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Applications Of Solid State Deuterium Nmr Spectroscopy To Organotransition Metal Complexes., Maria Ines Altbach Jan 1988

Applications Of Solid State Deuterium Nmr Spectroscopy To Organotransition Metal Complexes., Maria Ines Altbach

LSU Historical Dissertations and Theses

Solid-state deuterium NMR spectroscopy has been applied to several organometallic complexes. The deuterium quadrupole coupling constants for cis-($\mu$-C$\sp{\rm 2}$H$\sb{\rm 2}$)($\mu$-CO) (FeCp$\sp{\rm d=5}$(CO)$\rbrack\sb{\rm 2}$ (Cp$\sp{\rm d=5}$ = 5% deuteriated cyclopentadienyl), trans-($\mu$-C$\sp{\rm 2}$H$\sb{\rm 2}$) (MnCp$\sp{\rm d=2.7}$(CO)$\sb{\rm 2}$) $\sb{\rm 2}$ (Cp$\sp{\rm d=2.7}$ = 2.7% deuteriated cyclopentadienyl), and trans-($\mu$-C$\sp{\rm 2}$H$\sb{\rm 2}$ (CoCp$\sp{\rm d=5}$(CO)) $\sb{\rm 2}$ were determined by conventional solid-state deuterium NMR spectroscopy. The charges on the methylene bridging site for the three bridging methylene metal dimers were calculated by modeling the difference in deuterium quadrupole coupling constant between the sample and the reference molecule, (9,9-$\sp{\rm 2}$H$\sb{\rm 2}$)fluorene, by the change in occupancy of …

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A Theory And Empirical Test Of Retail And Office Lease Contracting., John Durland Benjamin Jan 1988

A Theory And Empirical Test Of Retail And Office Lease Contracting., John Durland Benjamin

LSU Historical Dissertations and Theses

This dissertation describes how retail and office lease provisions can be written to minimize contracting issues between transacting parties. Testable hypotheses regarding the allocation of risks and the reduction of opportunistic behavior, by lease provisions, are proposed. An empirical model which uses Rosen's (1974) well-known theory of hedonic price estimation is developed to test for the economic impact of specific retail and office lease provisions. Two unique data sets are employed which minimize non-provision variation between leased spaces. The first data set contains one hundred and three shopping center leases from neighborhood and community shopping centers which are all of …

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The Relationship Between Root Anatomic And Metabolic Responses To Soil Waterlogging In The Coastal Grass Spartina Patens., David Maaloe Burdick Jan 1988

The Relationship Between Root Anatomic And Metabolic Responses To Soil Waterlogging In The Coastal Grass Spartina Patens., David Maaloe Burdick

LSU Historical Dissertations and Theses

Spartina patens is a perennial grass that dominates dune, swale and marsh habitats in coastal Louisiana. Plant roots require oxygen for respiration and normal root function, and one of the most serious problems wetland plants encounter is the development of anaerobic conditions in the soil. The remarkable success of S. patens in habitats that occupy distant positions on a soil waterlogging gradient suggests either genetic differentiation or phenotypic adaptation among these populations. Field and greenhouse investigations were conducted to: (1) identify anatomic and metabolic soil waterlogging responses in Spartina patens, (2) examine the relationship between these responses, and finally (3) …

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Cogmir: A Computer Model For Knowledge Integration., Zheng Xin Chen Jan 1988

Cogmir: A Computer Model For Knowledge Integration., Zheng Xin Chen

LSU Historical Dissertations and Theses

Knowledge integration is an important topic for knowledge engineering. In this dissertation, we explore some aspects of knowledge integration, namely, accumulation of scientific knowledge and performing analogical reasoning on the acquired knowledge. Knowledge to be integrated is conveyed by paragraph-like pieces, these pieces will be referred to as documents. By incorporating some results from cognitive science, the Deutsch-Kraft model of information retrieval is extended to a model for knowledge engineering, which integrates acquired knowledge and performs intelligent retrieval. The resulting computer model is termed COGMIR, which stands for a COGnitive Model for Intelligent Retrieval. A scheme, named query invoked memory …

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Online Detection And Estimation Of Parameter Jumps., Fahmida Nilufar Chowdhury Jan 1988

Online Detection And Estimation Of Parameter Jumps., Fahmida Nilufar Chowdhury

LSU Historical Dissertations and Theses

In many dynamic systems, the parameters are subject to jumps at unknown points in time. The jumps may be the result of some change in the operating system, or plant failure. In this work a method has been developed for fast detection of these jumps and estimation of the post-jump values. The proposed method is called the Combined Filter Algorithm. It is based on the conventional Kalman filter. Single-sample hypothesis test is used to determine the presence or absence of jumps. Small jumps, missed by the hypothesis test, are traced by a Random Walk Model Kalman filter. This is made …

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An Initial Identification Of Parasite Specific Immune Responses In The Jird (Meriones Unguiculatus) Infected With Brugia Pahangi., Rita Gaskin Farrar Jan 1988

An Initial Identification Of Parasite Specific Immune Responses In The Jird (Meriones Unguiculatus) Infected With Brugia Pahangi., Rita Gaskin Farrar

LSU Historical Dissertations and Theses

Brugia pahangi infections in the jird (Meriones unguiculatus) is an accepted experimental model for the study of human lymphatic filariasis. Initial identification of parasite specific immune responses in jirds infected with B. pahangi are reported here. Antibody reactivity in sera from singly and multiply infected jirds against different stages of B. pahangi was determined using an indirect fluorescent antibody technique. All life cycle stages of the parasite were examined. Antibodies recognizing all stages were present in all serum samples. Removal of antibody reactivity by absorption of jird sera with B. pahangi antigen coated beads indicated that the antibodies were parasite …

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Crystal Structure Analyses Of An Organic Charge Transfer Salt, Three Bridged Binuclear Cobalt Complexes, And A Thiazole Derivative., Andrea Claire Greene Jan 1988

Crystal Structure Analyses Of An Organic Charge Transfer Salt, Three Bridged Binuclear Cobalt Complexes, And A Thiazole Derivative., Andrea Claire Greene

LSU Historical Dissertations and Theses

The structures of five compounds have been determined by single crystal x-ray diffraction. A non-superconducting organic charge-transfer salt, bis- (bis-(ethylenedithia)-tetrathiafulvalene) dibromoaurate(I), (BEDT-TTF)$\sb2$AuBr$\sb2$, was synthesized electrochemically, and crystallizes in monoclinic space group P2/c with Z = 2 and lattice constants 9 = 7.7950(21) A, b = 6.7150(6) A, c = 32.2000(31) A, $\beta$ = 100.508(13)$\sp\circ$; R = 0.0365 for 174 variables and 1904 observed reflections. One end of the independent BEDT-TTF molecule is disordered, a crystallographic feature which is common in these salts. Short sulfur-sulfur contact distances between cations are observed; however, the cations are not arranged in the same manner …

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Search For Allelochemicals In Rice (Oryza Sativa L.) And Structure Determination Of External Flavonoids Of Calamintha Ashei., Hidelisa Padua Hernandez Jan 1988

Search For Allelochemicals In Rice (Oryza Sativa L.) And Structure Determination Of External Flavonoids Of Calamintha Ashei., Hidelisa Padua Hernandez

LSU Historical Dissertations and Theses

The first part of this work was conducted to search for allelochemicals from the rice varieties PI346833 (moderately resistant) and Mars (susceptible) that may be responsible for resistance to fall armyworm, Spodoptera frugiperda (J. E. Smith) feeding. Mature tillers and seedlings were extracted with petroleum ether (PE), dichloromethane (DCM), acetone, methanol and water. The search for biological activity towards fall armyworm (FAW) was directed by growth inhibition bioassay. Significant antibiotic activity to FAW was observed with the PE and DCM crude extracts. Bioassay of the fractions of the PE and DCM extracts indicated that the fractions from PI346833 seedlings adversely …

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A Study Of The Interaction Of Peroxidic Tumor Promoters With Mitochondria., Christopher Henry Kennedy Jan 1988

A Study Of The Interaction Of Peroxidic Tumor Promoters With Mitochondria., Christopher Henry Kennedy

LSU Historical Dissertations and Theses

When micromolar concentrations of benzoyl peroxide (BPO) are added to rat liver mitochondria, inhibition of mitochondrial NADH-oxidase and succinoxidase is observed. The addition of a classical uncoupler of oxidative phosphorylation results in only partial release of this inhibition, suggesting that BPO inhibits both electron- and energy-transfer in mitochondria. Difference spectroscopy and artificial electron donor results indicate that BPO interacts at coupling site II between cytochromes b and c$\sb1$. BPO only yields radicals in mitochondria via inhibition of electron transport, which results in the formation of superoxide radicals. BPO also induces rapid, large-amplitude swelling of mitochondria; the swelling is dependent on …

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Synthesis, Transport And Assembly Of Wild Type And Mutant Precursors Of The Small Subunit Of The Chloroplast Enzyme Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase., Samuel John Landry Jan 1988

Synthesis, Transport And Assembly Of Wild Type And Mutant Precursors Of The Small Subunit Of The Chloroplast Enzyme Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase., Samuel John Landry

LSU Historical Dissertations and Theses

The small subunits of the chloroplast enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) are synthesized in the cytoplasm as precursors and transported into the organelle. The precursor (pS) of the small subunit (S) of RuBisCO contains an amino-terminal extension, the transit peptide, which is removed during or after transport into the chloroplast. The possible involvement of an RNA-containing component in transport of proteins into chloroplasts was investigated using a reconstituted system of pS translated in vitro and isolated chloroplasts. The post-ribosomal supernatant of the in vitro translation mixture and/or isolated chloroplasts were treated with ribonuclease prior to incubation for transport. Transport of pS …

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Intermolecular Interactions And The Theory Of Electron Transfer Between Hexaaquoiron Ions And Hexaammineruthenium Ions In Water., Paul James Magestro Jan 1988

Intermolecular Interactions And The Theory Of Electron Transfer Between Hexaaquoiron Ions And Hexaammineruthenium Ions In Water., Paul James Magestro

LSU Historical Dissertations and Theses

Theoretical studies of the electron transfer rates between hexaaquoiron(II) and (III) ions, and between hexaammineruthenium(II) and (III) ions in aqueous solutions have been undertaken using detailed representations of the interaction potentials and including the flexibility of the ligand geometry. This is done through an intuitive and efficient computational scheme involving tested site-site potentials for water and ammonia. The calculations on the ferrous-ferric electron exchange indicate that fluctuations in the configuration of the hydration shell are important and affect the rate significantly. In the hexaammineruthenium reaction, there is no evidence for any substantial contribution from this factor, although rates tend to …

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Transcribing For Solo Marimba., Christopher Scott Norton Jan 1988

Transcribing For Solo Marimba., Christopher Scott Norton

LSU Historical Dissertations and Theses

The marimba was ushered into the Western art world early this century. Thus, compositions written specifically for solo marimba are limited. One means of expanding the repertory is to transcribe for marimba. This study discusses the techniques of transcribing for solo marimba. It represents a synthesis of information drawn from examining, performing, and creating transcriptions for marimba. The introductory chapter covers related pertinent and prefatory topics such as a brief history of the marimba and its literature, the necessity for transcriptions, and the benefits and value of transcriptions and transcribing. The second chapter, which constitutes the body of the work, …

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The Combustion Of Carbon-Tetrachloride In A High Temperature Methane-Air Flame Environment., John Samuel Morse Jan 1988

The Combustion Of Carbon-Tetrachloride In A High Temperature Methane-Air Flame Environment., John Samuel Morse

LSU Historical Dissertations and Theses

Stable species concentration and temperature profiles are provided for a series of five CCl$\sb4$/CH$\sb4$/air flames studied on a flat flame burner at atmospheric pressure. A detailed description of the facility used to collect this data is given. This system includes a novel flue gas collection and treatment system. A new gas chromatographic technique used to analyze subatmospheric gas samples is described in detail. This technique utilizes gas syringes for sampling of selected C$\sb1$ and C$\sb2$ hydrocarbons and chlorinated hydrocarbons, as well as fixed gases. Stable species are sampled with aerodynamically cooled quartz microprobes. Temperature measurements are taken with uncoated 0.02 …

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Effectiveness Of The Healthy Weight Workshop On Weight Management Practices Of Paraprofessional Personnel Of The Cooperative Extension Service., Elizabeth S. Reames Jan 1988

Effectiveness Of The Healthy Weight Workshop On Weight Management Practices Of Paraprofessional Personnel Of The Cooperative Extension Service., Elizabeth S. Reames

LSU Historical Dissertations and Theses

This study was designed to investigate the effects of participation by black female paraprofessionals in a weight management workshop on selected indices including dietary intake, nutrition knowledge, exercise practices, eating behaviors, anthropometric measurements and sick leave hours used. Nineteen subjects from one urban site were selected to participate in the workshop and 18 subjects from another urban site served as the comparison group. Data were collected from both groups one week before, one week after and six months following the workshop. Measurements obtained before the workshop showed that the two groups had similar characteristics and pretest scores. Anthropometric measurements indicated …

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A Molecular Characterization Of An Escherichia Coli Restriction System Specific For 5-Methylcytosine-Containing Dna., Troy Kevin Ross Jan 1988

A Molecular Characterization Of An Escherichia Coli Restriction System Specific For 5-Methylcytosine-Containing Dna., Troy Kevin Ross

LSU Historical Dissertations and Theses

The McrB restriction system in Escherichia coli K-12 is responsible for sequence-specific recognition and inactivation of DNA containing 5-methylcytosine. A derivative of plasmid pUC8 with a 5.5-kilobase pair BglII-EcoRI restriction fragment from the E. coli K-12 chromosome, imparted the wild-type phenotype to the McrB$\sp-$ strain K802. The limits of the McrB region within this DNA fragment were defined by deleting portions of the 5.5-kb insert and assaying for McrB restriction of M.AluI-methylated DNA. Analyses of polypeptides encoded by the McrB region using a maxicell strain revealed that at least three proteins, having molecular weights of approximately 51,000, 39,000, and 33,000, …

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Studies On The Reactions Of Polycyclic Aromatic Hydrocarbons With Nitrogen-Dioxide In Aprotic Solvents., Giuseppe Luciano Squadrito Jan 1988

Studies On The Reactions Of Polycyclic Aromatic Hydrocarbons With Nitrogen-Dioxide In Aprotic Solvents., Giuseppe Luciano Squadrito

LSU Historical Dissertations and Theses

There is recent evidence that free radical nitration reactions occur in polluted urban air, and that the nitrated polycyclic aromatic hydrocarbons (NO$\sb2$-PAH) produced by this reaction pathway account for a substantial amount of the total NO$\sb2$-PAH found in ambient particulate organic matter. The nitration of PAH with nitrogen dioxide in solvents of low polarity has been studied as a model for the reactions occurring in the atmosphere (gas phase). While vast amounts of data are available for the electrophilic ionic nitration and its mechanism of reaction is considered well-established (and often included in sophomore Chemistry books), the literature documents relatively …

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An Investigation Of The Fungus, Balansia Cyperi Edg., And Its Effect On Purple Nutsedge, Cyperus Rotundus L., Mary Elizabeth Stovall Jan 1988

An Investigation Of The Fungus, Balansia Cyperi Edg., And Its Effect On Purple Nutsedge, Cyperus Rotundus L., Mary Elizabeth Stovall

LSU Historical Dissertations and Theses

This study was designed to investigate host specificity of the fungus Balansia cyperi Edg. on Cyperus rotundus L. (purple nutsedge) and to determine the effect of fungus presence on the biology and ecology of the sedge. Isolates of epiphytic Balansias from C. rotundus and C. virens had similar cultural characters, conidium morphology, and extracellular enzyme activity in artificial culture. However, B. cyperi from C. rotundus had a faster growth rate, greater conidium production, and higher temperature optimum than did the isolate from C. virens. Artificial infection of C. rotundus by B. cyperi from C. rotundus was far more successful than …

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