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Bioremediation Of Petroleum Hydrocarbons In Louisiana's Saltwater Marshes: Sediment Oxygen Demand Model., Won Sik Shin Jan 1998

Bioremediation Of Petroleum Hydrocarbons In Louisiana's Saltwater Marshes: Sediment Oxygen Demand Model., Won Sik Shin

LSU Historical Dissertations and Theses

Laboratory core studies were conducted to determine sediment oxygen demand (SOD) in petroleum hydrocarbon contaminated salt marshes. Natural degradation processes in salt marshes such as aerobic respiration, nitrification and sulfate reduction were investigated to quantify SOD. Oxygen demand in oiled/fertilized cores was greater than control and fertilized cores due to increased oxygen consumption by oil degradation and oxidation of reduced chemicals; sulfide and ammonium. SOD under non-flooded condition was greater than flooded condition due to an increased area of oxic-anoxic interface during air exposure. This may indicate that significant biodegradation of crude oil only occurs when the surface of the …

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Maximal Circuits In Matroids., Pou-Lin Wu Jan 1998

Maximal Circuits In Matroids., Pou-Lin Wu

LSU Historical Dissertations and Theses

Lovasz, Schrijver, and Seymour have shown that if a connected matroid M has a largest circuit of size c and a largest cocircuit of size c*, then M has at most 2c+c*-1 elements. A question of Oxley that has attracted considerable recent attention is whether there is an upper bound on the size of M that is polynomial in terms of c and c*. In particular, Bonin, McNulty, and Reid conjectured that 12cc* is such a bound. In Chapter 1, we prove this conjecture for an connected graphic and cographic matroids. In Chapter 2, we give a constructive description of …

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Teacher Selection Practices In Effective Elementary Schools Which Differ By Community Type And Socioeconomic Status Context., Amy Barham Westbrook Jan 1998

Teacher Selection Practices In Effective Elementary Schools Which Differ By Community Type And Socioeconomic Status Context., Amy Barham Westbrook

LSU Historical Dissertations and Theses

The current study investigated teacher selection in elementary schools which differ by school type, community type, and socioeconomic status (SES). The qualities sought, procedures utilized, and problems encountered by principals during teacher selection were examined. Statistical analyses were used to determine whether school types differ significantly on variables regarding teacher selection. The present study involved collecting both qualitative and quantitative data, and was conducted in four phases. In Phase I, all elementary schools in the state were classified by community type, student body SES, and "effective" and "typical" status. Phase II consisted of 12 site visits to "effective" schools which …

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The Effect Of Participation In The Occupational Safety And Health Administration's Voluntary Protection Programs On Injury/Illness Rates., Linda Diane Weems Jan 1998

The Effect Of Participation In The Occupational Safety And Health Administration's Voluntary Protection Programs On Injury/Illness Rates., Linda Diane Weems

LSU Historical Dissertations and Theses

The purpose of this study was to determine the effect participation in the Occupational Safety and Health Administration's (OSHA) Voluntary Protection Programs (VPP) has on injury/illness rates (IIR). Data was obtained from OSHA's Office of Cooperative Programs for the companies participating in the VPP for the years 1983 through 1997. This data was summarized and analyzed to satisfy this study's objectives. Objective 1 was to describe and compare the companies participating in OSHA's VPP and their IIR with the average IIR reported by the Bureau of Labor Statistics (BLS) for the industries for each year of the program's existence from …

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Association Of Environmental And Climatic Factors In The Epidemiology Of American Visceral Leishmaniasis In Northeast Brazil Using Remote Sensing And Geographical Information System Methods., Roland Alexander Thompson Jan 1998

Association Of Environmental And Climatic Factors In The Epidemiology Of American Visceral Leishmaniasis In Northeast Brazil Using Remote Sensing And Geographical Information System Methods., Roland Alexander Thompson

LSU Historical Dissertations and Theses

This study associated climatic and environmental factors with the incidence of visceral leishmaniasis (calazar) in Northeast Brazil. Remote sensing (RS) techniques permitted evaluation of spatial and temporal landscape features to stratify the region and define the target population for this vector-borne disease. The Municipality of Caninde, Ceara, Brazil was divided into 873-- 2 x 2 km2 squares centered on coordinates from a Universal Transverse Mercator projection (scale 1:100,000, 1994) and geo-referenced with 2 Landsat T.M. (TM) scenes (September 26, 1976 and July 2, 1996). The assignment of squares into foothills, plains or city strata was based on vegetative categories determined …

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An Estimation Of Rough Rice Basis In Southwest Louisiana, G Grant Giesler Jan 1998

An Estimation Of Rough Rice Basis In Southwest Louisiana, G Grant Giesler

LSU Agricultural Experiment Station Reports

No abstract provided.

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Gumbo Yearbook, Class Of 1998, Louisiana State University And Agricultural And Mechanical College Jan 1998

Gumbo Yearbook, Class Of 1998, Louisiana State University And Agricultural And Mechanical College

Gumbo Yearbook

The Gumbo yearbook chronicles the entire academic year at LSU. In words and especially photos, the Gumbo shows the people, places, and events that make each year unique. In addition to formal portraits of schools and departments, the book contains hundreds of snapshots of students with their friends and dozens of pages showcasing organizations.

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Hematite And Calcite Coatings On Fossil Vertebrates, B. A.O. Huiming, Paul L. Koch, Robert P. Hepple Jan 1998

Hematite And Calcite Coatings On Fossil Vertebrates, B. A.O. Huiming, Paul L. Koch, Robert P. Hepple

Faculty Publications

Hematite coatings are common on vertebrate fossils from Paleocene/Eocene paleosol deposits in the Bighorn Basin, Wyoming. In general, hematite coatings are found only on fossils and are limited to soils exhibiting hydromorphic features and moderate maturity. Pétrographie and isotopic evidence suggests that hematite and micritic calcite formed at nearly the same time in a pedogenic environment, whereas sparry calcite formed later at greater burial depths. The parent material of paleosols is rich in iron, supplying an ample source of iron for hematite formation. Decomposition of animal tissues around bones may enhance the weathering of iron-bearing minerals in soils surrounding carcasses, …

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First-Principles Determination Of Elastic Properties Of Casio3 Perovskite At Lower Mantle Pressures, Bijaya B. Karki, Jason Crain Jan 1998

First-Principles Determination Of Elastic Properties Of Casio3 Perovskite At Lower Mantle Pressures, Bijaya B. Karki, Jason Crain

Faculty Publications

We investigate the equation of state and elasticity of cubic CaSiO perovskite up to 140 GPa using the plane wave pseudopotential method within the local density approximation. The calculated equation of state parameters of the cubic phase are in excellent agreement with those from recent quasi-hydrostatic compression data and from all-electron linearized augmented plane wave calculations. We determine the elastic constant tensor of the mineral from the calculated stress-strain relations. The bulk modulus of CaSiO perovskite is similar to that of MgSiO perovskite, however, its shear modulus is much higher at pressures corresponding to the lower mantle. This suggests that …

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Apatite Fission Track Analysis Of Sites 959 And 960 On The Transform Continental Margin Of Ghana, West Africa, P. D. Clift, A. Carter, A. J. Hurford Jan 1998

Apatite Fission Track Analysis Of Sites 959 And 960 On The Transform Continental Margin Of Ghana, West Africa, P. D. Clift, A. Carter, A. J. Hurford

Faculty Publications

Four samples of sandstone from deformed Aptian-Albian sediments and their less deformed Turonian cover at Sites 959 and 960 on the Cote d'Ivoire-Ghana Marginal Ridge yielded sufficient apatite for fission track analysis. Reduced mean track length values of 12.42 ± 0.16 μm to 13.67 ± 0.11 μm indicate that measured central ages, which range from 88 ± 4 Ma to 113 ± 4 Ma, have undergone partial resetting and are therefore apparent ages. Stochastic modeling of the fission track age and length parameters indicate that the samples have a strong predepositional signal, slightly modified by minor levels of prolonged post-depositional …

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Interlaboratory Comparison Of Electron Probe Microanalysis Of Glass Geochemistry, J. B. Hunt, P. D. Clift, C. Lacasse, T. L. Vallier, R. Werner Jan 1998

Interlaboratory Comparison Of Electron Probe Microanalysis Of Glass Geochemistry, J. B. Hunt, P. D. Clift, C. Lacasse, T. L. Vallier, R. Werner

Faculty Publications

Tephrochronology commonly relies upon grain-discrete analysis of glass shards to reveal the subtle geochemical differences between tephras from past explosive volcanic eruptions. The use of electron probe microanalysis for this purpose is widely accepted by tephrochronologists. In addition, it is recognized widely that both precision and accuracy must be maximized, and that rigorous standardization procedures must be followed. In this paper, the performance of five electron microprobe centers used in the analysis of glass sharts from Leg 152 tephras is compared, using a geochemically homogeneous obsidian secondary standard. The results reveal the compatibility of most of the participatnats, supporting the …

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Compilation Techniques For Out-Of-Core Parallel Computations, M. Kandemir, A. Choudhary, J. Ramanujam, R. Bordawekar Jan 1998

Compilation Techniques For Out-Of-Core Parallel Computations, M. Kandemir, A. Choudhary, J. Ramanujam, R. Bordawekar

Faculty Publications

The difficulty of handling out-of-core data limits the performance of supercomputers as well as the potential of the parallel machines. Since writing an efficient out-of-core version of a program is a difficult task and virtual memory systems do not perform well on scientific computations, we believe that there is a clear need for compiler directed explicit I/O approach for out-of-core computations. In this paper, we first present an out-of-core compilation strategy based on a disk storage abstraction. Then, we offer a compiler algorithm to optimize locality of disk accesses in out-of-core codes by choosing a good combination of file layouts …

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Processing Of Value-Added Textile And Geotextile Products From Sugarcane And Kenaf., Ovidiu Romanoschi Jan 1998

Processing Of Value-Added Textile And Geotextile Products From Sugarcane And Kenaf., Ovidiu Romanoschi

LSU Historical Dissertations and Theses

Utilization of agricultural crops as alternate raw materials for many industries was investigated for both sugar cane and kenaf. Value-added products with textile and geotextile applicabilities were developed and their properties assessed in direct correlation with their final use. Bundles of fibers were extracted from the rind of sugar cane in three distinct steps: mechanical separation (using a Tilby separator), chemical extraction, and steam explosion. The process of fiber extraction was optimized for an atmospheric pressure alkali delignification, taking into account different factors such as: alkali concentration, reaction time, mixing, and steam explosion. Statistical techniques were used to study the …

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Characterization Of Seven Transmembrane Domain Receptor Gene Expression In Olfactory Receptor Neurons., Kathryn Medler Jan 1998

Characterization Of Seven Transmembrane Domain Receptor Gene Expression In Olfactory Receptor Neurons., Kathryn Medler

LSU Historical Dissertations and Theses

The expression of 7 transmembrane domain receptors in olfactory receptor neurons of the channel catfish, Ictalurus punctatus was characterized. Due to disagreements in the literature as to how many odorant receptor genes are expressed in olfactory neurons, this study directly measured the number of odorant receptor gene transcripts expressed in single olfactory neurons. Individual olfactory receptor neurons can express more than one receptor, with some neurons expressing at least 3 to 4 receptors. These findings correlate with electrophysiological evidence but disagree with conclusions based on in situ hybridization. Receptors similar to odorant receptors are also expressed in taste buds, indicating …

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Ultrafast Studies Of Reaction Dynamics., Zhenguo Feng Jan 1998

Ultrafast Studies Of Reaction Dynamics., Zhenguo Feng

LSU Historical Dissertations and Theses

The long range goal of this research is to understand the role of the solvent in condensed phase reactions. In the gas phase, great strides have been made towards understanding chemical reactivity at the level of individual quantum states. Liquid state reactions are not as well understood due to complicated many-body interactions with the solvent. Our approach has been to study simple reactions in solvents near their critical state. Here a small change in pressure, at constant temperature, allows a continuous change in solvent bulk density and viscosity, from near-liquid to gas-like properties. In this way reactions can be studied …

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Diagnosing Depression In Adolescents, Heather M. Villien Jan 1998

Diagnosing Depression In Adolescents, Heather M. Villien

Honors Capstones

No abstract provided.

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In Their Own Time: Four Women In The Fifteenth Century, Linda Mccomb Jan 1998

In Their Own Time: Four Women In The Fifteenth Century, Linda Mccomb

Honors Capstones

No abstract provided.

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The Effects Of Remorse In A Malpractice Case, Lahna M. Rung Jan 1998

The Effects Of Remorse In A Malpractice Case, Lahna M. Rung

Honors Capstones

No abstract provided.

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The Physiological And Psychological Responses To Submaximal Exercise At Different Times In Renal Disease Patients., Marta Amaral-Melendez Jan 1998

The Physiological And Psychological Responses To Submaximal Exercise At Different Times In Renal Disease Patients., Marta Amaral-Melendez

LSU Historical Dissertations and Theses

This study investigated cardiorespiratory, hematological, and psychological responses to acute submaximal exercise, and recovery in end stage renal disease patients. Five African-American males on hemodialysis, were randomly assigned to three exercise treatments (30 minutes on the treadmill at 60% VO$\sb2$ peak): pre dialysis (2 hours before), post dialysis (1 hour after), and off dialysis (24 hours after last dialysis). The cardiorespiratory (CR) variables were: ventilation (V$\sb{\rm E}$), oxygen consumption (VO$\sb2$), carbon dioxide production (VCO$\sb2$), respiratory exchange ratio (R), and kilocalories (KCAL/min). The hematological variables were: blood urea nitrogen (BUN), creatinine (Cr), albumin (Al), total protein (Tp), glucose (Gl), sodium (Na$\sp{++}$), …

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Form: The Fortran Object Recovery Model. A Methodology To Extract Object-Oriented Designs From Imperative Code., Bonnie Lynn Achee Jan 1998

Form: The Fortran Object Recovery Model. A Methodology To Extract Object-Oriented Designs From Imperative Code., Bonnie Lynn Achee

LSU Historical Dissertations and Theses

A majority of legacy systems in use in the scientific and engineering application domains are coded in imperative languages, specifically, COBOL or FORTRAN-77. These systems have an average age of 15 years or more and have undergone years of extensive maintenance. They suffer from either poor documentation or no documentation, and antiquated coding practices and paradigms (Chik94) (Osbo90). The purpose of this research is to develop a reverse-engineering methodology to extract an object-oriented design from legacy systems written in imperative languages. This research defines a three-phase methodology that inputs source code and outputs an object-oriented design. The three phases of …

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The Interactions Among The Subunits Of The Mcrbc Restriction System In E. Coli., Loganayaki Ganesh Jan 1998

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

LSU Historical Dissertations and Theses

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

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Detection Of Mechanisms Of Profenofos Resistance In The Tobacco Budworm, Heliothis Virescens (F.)., John Ambrose Harold Jan 1998

Detection Of Mechanisms Of Profenofos Resistance In The Tobacco Budworm, Heliothis Virescens (F.)., John Ambrose Harold

LSU Historical Dissertations and Theses

Biochemical and physiological mechanisms of profenofos resistance in laboratory and field populations of the tobacco budworm, Heliothis virescens (F.) were studied. High frequencies of profenofos resistance were recorded in all field-collected strains and were strongly correlated with esterase (EST) activity and moderately correlated with glutathione S-transferase activity. Mean levels of acetylcholinesterase (AChE) sensitivity to inhibition by chlorpyrifos oxon were lower in some field strains than levels in an insecticide-susceptible strain; however, AChE sensitivity and resistance were poorly correlated in all field strains. There was no correlation between resistance and the activities of P450-monooxygenase or glutathione S-transferase measured. Studies with laboratory-selected …

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A Conceptual And Empirical Approach For Valuing Biodiversity: An Estimate Of The Benefits Of Plant And Wildlife Habitat Preservation In The Tensas River Basin., Jack Coburn Isaacs Jan 1998

A Conceptual And Empirical Approach For Valuing Biodiversity: An Estimate Of The Benefits Of Plant And Wildlife Habitat Preservation In The Tensas River Basin., Jack Coburn Isaacs

LSU Historical Dissertations and Theses

This research estimated the passive use value of local species biodiversity in the Tensas River basin, a section of the Lower Mississippi River Valley. This research employed the contingent valuation method in eliciting willingness to pay for biodiversity conservation using the habitat needs of an umbrella species as a basis for valuation. This study designed and implemented the Lower Mississippi Valley Plant and Wildlife Survey for primary data collection. The sample included 1,351 households drawn from a hunting permit lottery conducted by the Tensas River National Wildlife Refuge and 3,044 households drawn at random from Louisiana, Arkansas, and Mississippi. The …

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Daniel Pratt Of Prattville: A Northern Industrialist And A Southern Town., Curt John Evans Jan 1998

Daniel Pratt Of Prattville: A Northern Industrialist And A Southern Town., Curt John Evans

LSU Historical Dissertations and Theses

This dissertation explores the life of Daniel Pratt, one of the South's most important industrialists. Daniel Pratt was born in Temple, New Hampshire on July 20, 1799. In 1821, he migrated to Jones County, Georgia, where he worked as a carpenter-architect for ten years. He married Esther Ticknor of Connecticut in 1827 Samuel Griswold hired Pratt in 1831 to superintend his cotton gin factory in Jones County. Two years later, Pratt migrated to Autauga County in central Alabama, where he started his own gin shop. In 1839, Pratt founded Prattville, located fourteen miles from Alabama's capital, Montgomery. The next year, …

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Evolutionary Effects Of Irradiation In Cataclysmic Variables., Patrick Joseph Mccormick Jan 1998

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

LSU Historical Dissertations and Theses

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

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An Exploratory Study Of The Consumer Behavior Of Working Adolescent Females., Diane Denais Sasser Jan 1998

An Exploratory Study Of The Consumer Behavior Of Working Adolescent Females., Diane Denais Sasser

LSU Historical Dissertations and Theses

Employment of high school students has been growing steadily since the mid-1960s (Cole, 1991). Today, more than 40% of all high school students who work are employed at least part-time (U.S. Bureau of Labor Statistics, 1995). Working adolescents may view their earnings as a sudden windfall of income to be used as discretionary income. This "premature affluence" may reinforce inappropriate consumer behaviors such as spending beyond means which may become established habits into their adult lives (Bachman, 1983). The cognitive development of these adolescents may be at the concrete operational thinking stage which inhibits them from handling adult behaviors in …

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Purification And Antioxidant Properties Of Rice Bran (Gamma)-Oryzanol Components., Zhimin Xu Jan 1998

Purification And Antioxidant Properties Of Rice Bran (Gamma)-Oryzanol Components., Zhimin Xu

LSU Historical Dissertations and Theses

A high purity $\gamma$-oryzanol was obtained from crude rice bran oil using a normal phase preparative scale HPLC. It was used in implementing a reverse phase HPLC method for separating each individual component of $\gamma$-oryzanol present in rice bran oil. Ten fractions were isolated in the reverse phase HPLC method. The ten components of $\gamma$-oryzanol were identified. Three of these, cycloartenyl ferulate, 24-methylene cycloartanyl ferulate, and campesteryl ferulate, were major components of $\gamma$-oryzanol. The yield of $\gamma$-oryzanol without saponification was significantly higher than that with saponification in solvent extraction. The solvent mixture with 50% hexane and 50% isopropanol (v/v.) at …

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The Structure And Stability Of Selected, 2-D Self-Gravitating Systems., Saied W. Andalib Jan 1998

The Structure And Stability Of Selected, 2-D Self-Gravitating Systems., Saied W. Andalib

LSU Historical Dissertations and Theses

Models of radially and vertically extended self-gravitating disks orbiting around a central point mass are relevant to the dynamics of astrophysical systems and are thought to be common in many galaxies. The gravity driven instabilities in these accretion disks are now believed to be a possible mechanism for star formation via disk fragmentation (Shu, Adams, & Lizano 1987, Adams, Rudin & Shu 1989; Christodoulou 1995). We quantify these regions of instability using a simple toroidal model of an accretion disk. We choose the two-dimensional axisymmetric, incompressible slender disks to examine and map out these principal modes of gravity driven instabilities. …

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Identification Of Antigens Of Edwardsiella Ictaluri, The Causative Agent Of Enteric Septicemia Of Catfish (Esc)., Michelle Marie Moore Jan 1998

Identification Of Antigens Of Edwardsiella Ictaluri, The Causative Agent Of Enteric Septicemia Of Catfish (Esc)., Michelle Marie Moore

LSU Historical Dissertations and Theses

Edwardsiella ictaluri, causative agent of enteric septicemia of catfish (ESC), is the primary bacterial pathogen of commercially produced channel catfish (Ictalurus punctatus). The purpose of this study was to make progress towards development of a successful ESC vaccine by generating and characterizing a pool of E. ictaluri antigens and determining if they were protective against ESC in catfish. Antigenic protein expression was evaluated in E. ictaluri cells under different conditions of growth using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and western blotting with pooled convalescent catfish serum (CCS). Results showed protein bands separated by one-dimensional PAGE may consist of one or …

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Structural Characterization Of Beta Carbonic Anhydrases From Higher Plants., Michael H. Bracey Jan 1998

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

LSU Historical Dissertations and Theses

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

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