Digital Commons Network^™

Synthesis Of Phosphonopeptides And Alpha, Alpha-Dialkylated Amino Acid-Rich Peptides., Sheila Denise Rushing

LSU Historical Dissertations and Theses

Peptides and peptide analogs are central to the understanding of biological and biochemical phenomena as well as in the development of new pharmaceutical agents. This research encompasses two classes of peptide mimetics: phosphonopeptides and short, amphipathic peptides rich in alpha,alpha-disubstituted amino acids (alphaalphaAA). The focus of the first part of the peptide analog project was on the preparation of sterically-hindered phosphonamide and thiophosphonamide dipeptides. Conditions were developed, based on our P(III) synthetic approach, for the preparation of the phosphonamide dipeptides, Cbz-CyhGly psi [P (O) (OpNb) NH] Trp-NH2 and Cbz-CyhGly psi [P (O) (OpNb) NH] Trp-OMe, which were previously unattainable by …

Molecular Systematics Of Eastern Cottonwood Using Aflp And Rapd Markers., Xiaohong Ma

LSU Historical Dissertations and Theses

Eastern cottonwood (Populus deltoides Bartr.) is the fastest growing tree in southeastern United States with great potential as a biomass source. DNA-based molecular marker techniques are playing increasingly important roles in elucidating genetic diversity within species. Amplified fragment length polymorphism (AFLP) and random amplified polymorphic DNA (RAPD) markers were employed to study genetic relationships among 57 clones from subregion Lower Mississippi river, West Central, and West Gulf. A total of 101 polymorphic RAPD markers were amplified from 14 primers. Six AFLP primer pairs resulted in a total of 457 polymorphic markers. Both RAPD and AFLP markers were able to uniquely …

Removal Of Manganese In Reservoir Tailwaters As A Function Of Reservoir Operations And River Substrate., Steven Lane Ashby

LSU Historical Dissertations and Theses

Removal of reduced manganese in aqueous systems has been described as a two-step process that incorporates a chemical or abiotic step followed by or continued with microbially mediated processes. Field and laboratory studies were conducted to describe the removal of manganese from reservoir tailwaters and partition the abiotic and microbial removal processes. Manganese removal was measured in controlled raceways and in microcosms with four sizes of substrate (cobble, 2.00 to 0.50 mm, 0.50 mm to 0.063 mm, and less than 0.063 mm). Sodium azide was used to inhibit biological uptake. An exponential decay model and a hyperbolic decay model were …

Structure And Function Studies Of De Novo Peptides Containing Novel Amino Acids., Ted Joseph Gauthier

LSU Historical Dissertations and Theses

A series of amphipathic peptides rich in alpha,alpha-disubstituted amino acids (alphaalphaAA's) was synthesized and studied for antimicrobial activity and helix preferences in various solvent systems. In addition, a constrained lactam dipeptide amino acid was synthesized and incorporated into a peptide to examine beta-sheet dimer formation. Several short, amphipathic, 310- and alpha-helical peptides containing 80% alphaalphaAA's were synthesized using various combinations of 1-aminocyclohexane-1-carboxylic acid, alpha-aminoisobutyric acid, and 4-aminopiperidine-4-carboxylic acid. The peptides showed direct antimicrobial activity against E. coli and S. aureus. In addition, several of the peptides showed in vivo and in vitro activity against Brucella abortus and Mycobacterium chelonei. Studies …

Gaps In College Biology Students' Understanding Of Photosynthesis: Implications For Human Constructivist Learning Theory And College Classroom Practice., Phyllis Baudoin Griffard

LSU Historical Dissertations and Theses

The main research question of this study was: What gaps in biochemical understanding are revealed by a range of university introductory biology students as they work through a critically acclaimed multimedia program on photosynthesis, and what are the corresponding implications for elaboration of the Ausubel-Novak-Gowin Learning Theory (ANG, now Human Constructivism)? Twelve students, mixed for ability, gender and ethnicity, were recruited from two sections of "Bio 101." Before and after instruction in photosynthesis, in-depth clinical interviews were conducted during which participants completed a range of cognitive tasks such as sorting, concept mapping, explaining and predicting. Some tasks involved interacting with …

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

LSU Historical Dissertations and Theses

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

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

Directed Search In K-System Reconstruction., Christopher W. Branton

LSU Historical Dissertations and Theses

K-systems analysis is a factor analysis technique created through the generalization of key reconstructability analysis definitions and algorithms. The method is applied to functions on systems of discrete variables to discover a set of factors which can explain the bulk of the function's variation from the mean. K-systems analysis uses principles of information theory to reveal interactions which are often masked by the assumptions implicit in traditional methods. The method has been used successfully to analyze systems in several disciplines. Despite the success of k-systems analysis, obstacles to the creation of a mature methodology still exist. Some issues and open …

Serological And Molecular Biological Studies Of Marine Predator-Prey Systems., Marilyn J. Hoyt

LSU Historical Dissertations and Theses

Two aspects of species identification were addressed; a molecular approach to identify anchovy larval and serological methods for prey detection in predator gut washes. Analysis of the pattern of restriction fragments of mitochondrial DNA (mtDNA) from adult anchovies from the Gulf of Mexico was employed to speciate four anchovy species. MtDNA isolated from white muscle of adult Anchoa mitchilli, A. hepsetus, A. nasuta and Engraulis eurystole produced an amplified 2.4 Kb DNA product when primers for NADH dehydrogenase 5 and 6 genes were used in polymerase chain reactions (PCR). Digestion of the amplified sequence with Dpn II produced a unique …

Alcohol, Assault And Area: An Examination Of Alcohol Availability And Crime In East Baton Rouge Parish, Louisiana., Stephen Edgar Costanza

LSU Historical Dissertations and Theses

An association between alcohol and crime has been proposed for over forty years in Criminological Literature. The research conducted in this dissertation uses pooled data on alcohol, neighborhood characteristics, and crime in East Baton Rouge Parish, Louisiana. The intention of the paper is to further augment our understanding of the alcohol-crime relationship by studying it at the macro-level. Using 278 Baton Rouge block groups as units of analysis, the results of the study confirm that the presence of package-only alcohol outlets have significant effects on assault and robbery within neighborhoods.

Relationship Of Self-Injurious Behavior And Aggression To Social Skills In Persons With Severe And Profound Mental Retardation., Dee Duncan

LSU Historical Dissertations and Theses

In the literature, self-injurious behavior and aggression are often lumped together collectively as maladaptive behaviors. This study examined the social skills characteristics between persons with self-injurious behavior, aggression and a control group using the Matson Evaluation of Social Skills in Persons with Severe and Profound Retardation (MESSIER). Persons engaging in self-injurious behavior were significantly different from persons engaging in aggression as well as from the control group on five of the six subscales. The self-injury group had lower scores on subscales measuring positive behaviors and higher scores on subscales measuring negative behaviors. As expected for persons engaging in aggression, scores …

Phylogeny Of The Characeae (Charophyta) And Biogeography Of Chara (Characeae) Inferred From Ribosomal Rna Genes., Susan T. Meiers

LSU Historical Dissertations and Theses

This dissertation examined generic, subsection, and infraspecific aspects of the phylogeny of the Characeae, and biogeography of Chara subsections and Chara haitensis. These relationships were inferred from cladistic and maximum likelihood analyses of sequence data for 18S and ITS regions of nuclear-encoded ribosomal RNA genes. Morphologically-based phylogenetic hypotheses of Wood and Imahori (1965) and Khan and Sarma (1984) concerning the six extant members of Characeae were tested. The analyses supported: monophyly of family Characeae, tribe Chareae, and of Lamprothamnium; placement of Nitellopsis basal to tribe Chareae; and an unresolved relationship between Lamprothamnium and Chara. Neither the hypothesis of Wood and …

Spatial Distribution And Sequential Sampling Of The Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, In Louisiana., Mark Alan Muegge

LSU Historical Dissertations and Theses

Studies were conducted in Louisiana to determine the spatial and temporal distribution of rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, adults, eggs, larvae and pupae in drill-seeded rice. In addition, three sequential sampling plans, Kuno's fixed precision sequential sampling plan, the sequential probability ratio test (SPRT), and 2-SPRT, were developed and evaluated to establish an accurate and economically efficient sampling plan for RWW larvae in drill-seeded rice in Louisiana. Values obtained for the aggregation indices, b, from Taylor's power law, $\beta$, from Iwao's patchiness regression and, k, from the negative binomial distribution indicated that RWW larvae were nearly randomly distributed …

Dinitropyrenes: Nitroreduction Processes And Evaluation Of Indices Of Exposure., Matthew Jerome Krautmann

LSU Historical Dissertations and Theses

Investigations were conducted to identify biomarkers of exposure to dinitropyrenes (DNPs), which are mutagenic and carcinogenic residues of incomplete combustion. One possible biomarker, a DNP-protoporphyrin IX adduct, was not found in analytically useful quantities in liver tissue or in bile. Clastogenicity, a biomarker of effect, also was found to be absent in marrow cells following subchronic exposure of rats to DNPs by gavage. Solubility studies, used as a basis for dosing guidelines, revealed that DNPs are relatively insoluble in both aqueous and lipid tissue compartments. Calculated log P values indicated that the reduced metabolites of DNPs probably are more soluble …

Characterization Of Physiological Changes In Roots Grown In Spaceflight Conditions: A Comparison Of Nutrient Delivery Technologies., David Marshall Porterfield

LSU Historical Dissertations and Theses

The best strategy for providing food and maintaining the environment on long-duration space missions is a bioregenerative life support system based on the growth of higher plants. Before such a system can be implemented, a better understanding of plant growth in space will have to be achieved. Little is known about the role of gravity-dependent physical processes in normal physiological function. A series of ground-based and spaceflight experiments was conducted to examine root oxygen availability in microgravity nutrient delivery systems. In spaceflight experiments Arabidopsis thaliana (L.) Heynh. plants were analyzed for changes in root medium redox potential and root alcohol …

The Biology And Ecology Of The Yellowmargined Leaf Beetle, Microtheca Ochroloma Stal, (Coleoptera: Chrysomelidae) On Crucifers., Abdullahi Olod Ameen

LSU Historical Dissertations and Theses

The biology and ecology of the yellowmargined leaf beetle, Microtheca ochroloma Stal, were studied on cabbage, Brassica oleracea var capitata L., collard, B. oleracea var acephala L., mustard, B. juncea Cosson, turnip, B. rapa L., and radish, Raphanus sativus L. The life cycle of the beetle consists of an egg stage, four larval instars, prepupal, pupal and adult stages. There were no significant differences in the effect of host plant on duration of development of immature beetles (p = 0.3353). The mean duration of development from oviposition to adult emergence ranged from 26.6 d on turnip to 27.5 d on …

Isolation, Structural Elucidation And Structure-Activity Studies Of Natural Products From Regional Plants Of The Asteraceae., Tiansheng Lu

LSU Historical Dissertations and Theses

In a biochemical systematic study of the plant family Asteraceae combined with a search for bioactive natural products, the isolation and structural elucidation of secondary metabolites from seven plant species is reported. Investigation of the roots of Solidago canadensis provided six known and one new clerodane diterpenes related to kolavenic acid and five known matricaria ester-type polyacetylenes. The roots and aerial parts of Solidago rugosa afforded the known diterpenes kolavenol, hardwickiic acid, ($-$)-kaur-16-en-19-oic acid, (+)-manool, (+)-3$\beta$-hydroxymanool, manoyl oxide and ent-abietic acid and the new labdane diterpene, (+)-18-tigloyloxymanool, plus four new ent-abietane diterpenes. The isolation of two new and eight known …

A New Therapeutic Concept Based On Hyperstabilization Of Sense-Antisense Duplexes., Dae-Yong Kim

LSU Historical Dissertations and Theses

We proposed that known helix-stabilizing, minor-groove binding agents such as CC-1065 and its analog, U-71,184, might be feasibly targeted to specific mRNA by tethering them to antisense oligonucleotides. The CC-1065-tethered antisense oligonucleotide might be hyperstabilized to the target mRNA and arrest the translation of mRNA. Our hypothesis is that these agents can bind and increase the stability of RNA-DNA duplexes which may occur between mRNA and antisense oligonucleotides. To verify our hypothesis, we evaluated the ability of CC-1065, U-71,184, and distamycin A to bind and hyperstabilize the 20-mer sense sequence (5$\sp\prime$-TTACTTCAGTTATGAGACCA-3$\sp\prime)$ duplexed with complementary (antisense) oligonucleotide sequence made with phosphodiester …

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 …

Methyl Oleate Ozonides In Aqueous Micelles: Formation, Stability, And Initiation Of Lipid Peroxidation, And, Relative Antioxidant Efficiencies In Aqueous Micelles Of Anionic And Cationic Surfactants., Mingdan Wu

LSU Historical Dissertations and Theses

Ozonation of methyl oleate has been shown for the first time to form ozonides in aqueous micelles of sodium dodecyl sulfate (SDS) and in L-$\alpha$-distearoyl-phosphatidylcholine (DSPC) liposomes. The total yield of ozonides in 0.02 M SDS micelles exposed to 26 ppm ozone at pH 7.4 and 22$\sp\circ$C is 11.1%. This 11.1% consists of 7.5% of the normal ozonide (MOO2), ca. 4.2% of trans-isomer and ca. 3.3% of cis-isomer, and the rest 3.6% is accounted for by the cross ozonides (MOO1 and MOO3). Regarding the hydrolytic stability of the ozonides under physiologically relevant conditions (e.g., pH 7.4 and 37$\sp\circ$C), the half-lives …

In Vitro Studies On Cigarette Smoke-Mediated Damage To Human Alpha-1-Proteinase Inhibitor., Mark Dennis Evans

LSU Historical Dissertations and Theses

The effect, in vitro, of water soluble components of the particulate phase of cigarette smoke on the elastase inhibitory capacity (EIC) of human alpha-1-proteinase inhibitor ($\alpha\sb1$PI) is studied. Basic features of aqueous cigarette tar extract-mediated damage to $\alpha\sb1$PI are presented, as are mechanistic studies addressing the identities of damaging species and the nature of damage to $\alpha\sb1$PI. Aqueous cigarette tar extract (ACT) causes a slow loss of EIC, and retains this $\alpha\sb1$ PI damaging ability for hours. The damage to $\alpha\sb1$PI by ACT is dependent on its hydrogen peroxide content. Hydroxyl radicals or hypervalent metal species in the homogeneous phase …

Molecular Biological Studies On The Degradation Of Diphenyl Ethers By Bacteria., Hung-Ming James Liaw

LSU Historical Dissertations and Theses

Microbial degradation of diphenyl ethers was studied utilizing several different approaches. The first approach was to isolate mutants from a ligninolytic Erwinia sp. by conventional mutagenesis and selection. A copper-resistant mutant, designated as Erwinia sp. CU3614, was isolated and characterized to be capable of degrading diphenyl ethers as well as one dibenzo-p-dioxin in the presence of copper ions. Isolation of Tn5 transposon-induced mutants of Erwinia sp. CU3614, which lost degradation ability, demonstrated that in all probability a copper-associated activity in the biotransformation of aromatic ethers was involved. In order to study the degradation at the molecular biological level, a 2.1 …

Fine Scale Velocity Measurements In A Turbulent Jet In A Confined Crossflow., Julie Ann Mathis

LSU Historical Dissertations and Theses

Measurements of the fine scale velocity field are made for a turbulent jet in a confined crossflow. With a crossflow velocity of 10.0 m/sec, jet-to-crossflow velocity ratios of 1, 2 and 4 are examined. Velocity measurements are obtained by laser velocimetry. The velocimetry system consists of a 15mW laser with a fringe mode optics setup, operated in the backscatter mode. Signal processing is accomplished with a tracker processer. At each measuring location, 28,400 velocity readings are obtained at a sampling frequency of 38,460 sec$\sp{-1}$. Calculations include construction of autocorrelation functions, Kolmogorov-normalized energy spectra and their moments, skewness and flatness of …

Studies On The Seasonal Biology, Influence Of Temperature On Immature Stages, And Damage To Field Corn By The Chinch Bug, Blissus Leucopterus Leucopterus (Say)., Jose Fermin Negron-Segarra

LSU Historical Dissertations and Theses

Seasonal biology studies of the chinch bug, Blissus leucopterus leucopterus (Say), indicated movement out of overwintering sites in April in central Louisiana. Mass emergence appeared to be influenced by ambient temperatures of 26.7$\sp\circ$C or above. Overwintering populations attacked corn and wheat simultaneously and field invasions were predominantly by flight. Peak overwintering populations in Andropogon virginicus L. occurred in November and December. Overwintering populations decreased consistently beginning in January and culminated with spring emergence. Fall migrations back to overwintering sites began in September and peaked in October. Studies on the effect of temperature on the immature stages of this insect indicated …

Free Radical Production From Criegee Ozonides., James Conrad Ewing

LSU Historical Dissertations and Theses

Allylbenzene ozonide (ABO), a model for poly-unsaturated fatty acid (PUFA) ozonides, is shown to initiate the autoxidation of methyl linoleate (18:2ME) at 37$\sp\circ$C under 760 torr of oxygen. This process is inhibited by d-alpha-tocopherol ($\alpha$-T) and 2,6-di-tert-butyl-4-methylphenol (BHT). Rates of initiated autoxidation were measured by appearance of conjugated diene (C.D.) and oxygen-uptake experiments; rates are proportional to the square root of ABO concentration, implying that the usual free radical autoxidation rate law is obeyed. Activation parameters for the thermal decomposition of ABO were determined under N$\sb2$ in the presence of radical scavengers and found to be E$\sb{\rm a}$ = 28.2 …

Nitrone Spin Traps For Biological Studies. (Volumes I And Ii)., William Reeves Huie

LSU Historical Dissertations and Theses

A variety of aldonitrones for spin-trapping investigations have been synthesized, purified, and characterized. The alicyclic 5-member ring nitrones 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (TMPO) and its long-chain derivatives were prepared in 3 or 4 steps. The reaction steps involved a Michael addition to yield the $\gamma$-nitrocarbonyl compound, subsequent mild reduction with zinc and aqueous ammonium chloride to yield the cyclic intermediate nitrone, a Grignard addition reaction to give the hydroxylamine, and finally copper-catalyzed aerial oxidation of the hydroxylamine to provide the aldonitrone. Poor overall yields were obtained. In contrast, the acyclic aromatic nitrone $\alpha$-phenyl-N-tert-butyl nitrone (PBN) and its derivatives were prepared …

The Behavioral Ecology Of The First Instar Southern Green Stink Bug, Nezara Viridula (L.) (Aggregation, Pheromone, Embryo, Egg, Nymph)., Jeffrey Alan Lockwood

LSU Historical Dissertations and Theses

Outer row embryos of the southern green stick bug, Nezara viridula (L.), orient toward the center of the egg mass; inner row embryos do not. Embryonic orientation was mediated by stimuli provided by the glue which holds the egg mass together. Physical and chemical orientation cues associated with the glue were present only on the inner surfaces of outer row eggs; other eggs received no such differential stimuli and therefore oriented as a function of the oviposition behavior of the female. Embryonic orientation assured that upon hatching, outer row nymphs received the stimulation necessary for arrestment and inclusion in the …

The Life Cycle And Ecology Of Octospiniferoides Chandleri Bullock 1957 (Acanthocephala)., David Joseph Demont

LSU Historical Dissertations and Theses

No abstract provided.

The Coccinellidae Of Louisiana (Insecta: Coleoptera)., Joan Beggs Chapin

LSU Historical Dissertations and Theses

No abstract provided.

Tabanidae (Diptera): Some Systematic Aspects., Mac Anthony Tidwell

LSU Historical Dissertations and Theses

No abstract provided.

A Laboratory And Greenhouse Evaluation Of Typhlodromus Fallacis (Gar.) Asa Predator Of Tetranychus Spp., John Cole Smith

LSU Historical Dissertations and Theses

No abstract provided.