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Age-Related Changes In The Cardiorespiratory Response To Exercise And Physical Training, Joan Elizabeth Himann

Digitized Theses

The age-related decrease in cardiorespiratory fitness in the elderly has been attributed to the aging process and to reduced activity levels. The cardiorespiratory response to exercise across the ages (19-102y) was examined in order to describe the age-related rate of decline of cardiovascular function, study the effect of an exercise training program on this decline and discover whether the control mechanisms of the integrated response to exercise are affected by aging.;Both men and women showed a curvilinear decrease in self-selected walking speed with age (19-102y). In the older age range ({dollar}>{dollar}60y), minimal oxygen consumption (VO{dollar}\sb2{dollar}max) was predicted best by …

The Breeding Ecology Of Pink Salmon (Oncorhynchus Gorbuscha Walbaum) From The Carp River, Eastern Lake Superior, Douglas Brian Noltie

Digitized Theses

Although inadvertently introduced to North American's Laurentian Great Lakes, pink salmon (Oncorhynchus gorbuscha) now constitute the world's only self-perpetuating freshwater population of this species. Their proliferation and growing impact on the extant fish fauna are elevating the species to one of considerable importance here. Despite this, the reproductive ecology of Great Lakes populations remains largely unknown. This study of the pink salmon breeding in the Carp River, a tributary to eastern Lake Superior, is a response to the need for this information. Considered are their upstream migration patterns, fish size and condition variation, migrant reproductive maturity and gonadal investment, male …

Socio-Environmental Factors Associated With Length Of Gestation And Infant Birth Weight Among A Teenage Sample, Sandra Elizabeth Nuttall

Digitized Theses

Infant birth weight and length of gestation are associated with a variety of health outcomes for the infant. Birth weight, in particular, is most closely associated with neonatal and postneonatal mortality as well as a number of other health consequences.;The present study has considered some promising socio-environmental factors and their relationship to length of gestation and infant birth weight. These factors included social stressors, supportive relationships, self esteem and personal competence. As well, this study examined a potential intervening role for those variables in the relationship of maternal age and marital status with study outcomes.;The study group consisted of 204 …

Structure-Function Relationships In The Rna Binding Activities Of Ribosomal Protein S20 Of Escherichia Coli, Brooke Cameron Donly

Digitized Theses

The ribosomal protein S20 of Escherichia coli is one of only six small subunit proteins capable of binding independently to 16S rRNA. To define the regions of S20 required for binding to 16S rRNA, the binding of S20 and a number of C-terminal deletion mutants to 16S rRNA were measured. Mutant S20s constructed using recombinant DNA technology were synthesized in vitro by coupled transcription-translation and assayed directly. The affinity of S20 produced in vitro for 16S rRNA was found to be 1.2 {dollar}\times{dollar} 10{dollar}\sp7{dollar} M{dollar}\sp{lcub}-1{rcub}{dollar} using a gel filtration assay. Removal of just 6 residues from the C-terminus of the …

The Role Of The Subfornical Organ In The Control Of Cardiovascular Function And Fluid Homeostasis, Michael Bentov Gutman

Digitized Theses

Increased circulating levels of angiotensin II (ANG II) are known to act at the subfornical organ (SFO) to produce increases in arterial pressure, drinking and secretion of arginine vasopressin (AVP). These studies were done to investigate whether the SFO projections to the nucleus medianus (NM), supraoptic nucleus (SON) and paraventricular nucleus of the hypothalamus (PVH) mediate these responses.;Experiments done in urethane anesthetized rats showed that the SFO was the most sensitive area in the region for eliciting cardiovascular responses consisting of short and long latency increases in arterial pressure, when electrically stimulated or microinjected with L-glutamate. Ganglionic blockade abolished the …

Studies On The Regulation Of Oocyte Maturation In The Rat With Assessment By In Vitro Fertilization And Fetal Development, Barbara Catharine Vanderhyden

Digitized Theses

The purposes of this study were: (1) to develop techniques for in vitro maturation of rat oocytes which would permit fertilization and normal embryonic development, and (2) to investigate the role of somatic cell-germ cell interactions, and hormonal influences, in the physiological regulation of oocyte maturation as assessed by these techniques.;Procedures for in vitro fertilization (IVF) of rat oocytes were developed and validated by transferring the resulting embryos to recipient females. Although embryos resulting from IVF were less successful in establishing pregnancy than appropriate in vivo fertilized controls, optimization of culture and transfer techniques enabled minimization of embyronic losses and …

Polypeptide Synthesis In Response To 20-Hydroxyecdysone, With Particular Reference To Calcium Binding Proteins, In The Epidermis Of A Larval Insect, Yves Ouellette

Digitized Theses

Epidermal cells respond to 20-hydroxyecdysone (20HE) by altering their morphology, rate of proliferation and level of cell-to-cell communication. This response depends on polypeptide synthesis.;To study changes in polypeptide synthesis induced by 20HE, epidermal polypeptides from the midinstar larvae of the mealworm Tenebrio molitor were separated by one- and two-dimensional polyacrylamide gel electrophoresis (PAGE). {dollar}\sp{lcub}35{rcub}{dollar}S-methionine-labelled (non-cuticular) polypeptides were extracted from cells incubated either in the absence or presence of 2 ug/ml 20HE (4 uM) for 14-16 h in vitro. Cells incubated with the hormone incorporated 28% more label into polypeptides. Over 250 polypeptides were detected in total cell lysates by this …

Genetic Control Of Immune Responsiveness To The Avian Coccidium Eimeria Tenella, Robert Andrew Clare

Doctoral Dissertations

Specific inbred lines of chickens expressing different major histocompatibility (B) complex haplotypes were studied for their immunogenetic response to the avian coccidium Eimeria tenella and genetically-engineered antigens cloned from this parasite species. The relative influence of the B-F vs. B-G chromosomal regions on innnate resistance and immunity to E. tenella was studied among six B-F/B-G recombinant hosts. F$\sb1$ chicks of similar genotypes, $B\sp{\rm R3}$ and $B\sp{\rm R4} (B\sp{\rm F2-G23}B\sp{17}$), gained significantly more weight than those with $B\sp{\rm R1}(B\sp{\rm F24-G23}B\sp{17})$ and $B\sp{\rm R5} (B\sp{\rm F21-G19}B\sp{17})$ following exposure to a single high dose of 25,000 oocysts, although no differences in cecal lesion …

Investigations Into Bovine Luteolytic Mechanisms Utilizing A Long-Term Cell Culture System, Shari Jean Litch

Doctoral Dissertations

Luteal regression in the cow occurs every cycle in which pregnancy does not occur. The agent which induces luteolysis is a uterine prostaglandin, PGF$\sb{2\alpha}$, although the mechanism of its action remains unknown. The purpose of this study was to investigate the mode of action of PGF$\sb{2\alpha}$ in a long-term, serum-free culture system of bovine luteal cells. Experiment I investigated the influence of LH and PGF$\sb{2\alpha}$ on 3$\beta$-HSD presence in cultured luteal cells. Total numbers of cells dropped slightly throughout the 8 day culture. Numbers of 3$\beta$-positive cells also dropped in all treatment groups. 3$\beta$-HSD was best maintained in the presence …

Chelation, Transport And Physiological Roles Of Iron In Aquaspirillum Magnetotacticum, Lawrence Charles Paoletti

Doctoral Dissertations

Iron is a required nutrient for all living organisms. The magnetic spirillum, Aquaspirillum magnetotacticum possesses the ability to transform this metal to intracellular magnetite. Presented in this dissertation are studies relating to iron chelation and transport mechanisms used by this Gram negative bacterium. In addition, physiological roles of iron, specifically in respiration and the cellular localization of iron-containing respiratory components are also addressed.

Peptide And Amine Actions On The Neurogenic Limulus Heart: Biochemical Mechanisms Of Modulation, James Richard Groome

Doctoral Dissertations

The biochemical basis underlying the chronotropic and inotropic effects of peptides and amines on the neurogenic heart of the horseshoe crab, Limulus polyphemus, was investigated. This study focused on the role of cyclic nucleotide and phosphatidylinostiol metabolism in specific actions of amines and peptides endogenous to the Limulus nervous system. Biochemical and electrophysiological analyses of amine and peptide actions on specific cellular targets within the neurogenic heart network were performed to characterize the intracellular mechanisms responsible for the excitatory effects of these neuromodulators.

Octopamine and the catecholamines dopamine, norepinephrine and epinephrine utilize the second messenger cyclic AMP at multiple cellular …

Regulation Of Zooplankton Vertical Migrations By Light, Food, And Fish, Elizabeth Susan Mclean

Doctoral Dissertations

The regulation of zooplankton vertical migration has been attributed to the physical environment, and, more recently, to biological factors. This study evaluated the influence of light, food and fish on vertical migration. Laboratory experiments quantified changes in vertical migrations of Daphnia pulex in tall columns in response to short term changes in food concentration and the presence of a fish, under a wide range of natural light conditions.

A stimulus-threshold model predicted the time of the start of migration from a threshold rate of relative light intensity change. Hypotheses that migrations follow isopleths of light intensity, and that velocity of …

An Origin Of Transfer Of The Vwa Plasmid Of Yersinia Pestis, John R. Allen

Doctoral Dissertations

The Vwa plasmid (pYV019::Tn5) of Yersinia pestis was transduced from Escherichia coli LE392 to several F-containing strains of E. coli. Agarose gel electrophoresis of plasmid extracts prepared from the transductants revealed that both plasmids coexisted in these cells, at least to some degree, as autonomous cytoplasmic elements. Transductants demonstrably sensitive to the male specific phage MS-2 and thus carrying the F plasmid were used as donors in matings with several F$\sp-$strains. The results of these matings indicated that the Vwa plasmid was mobilized and cotransferred at a low frequency (0.001%) along with F. Agarose gel electrophoresis of plasmid extracts prepared …

Genetics And Physiology Of Cold Tolerance In Muskmelon (Cucumis Melo L), Mark Gordon Hutton

Doctoral Dissertations

Five hundred muskmelon accessions were evaluated for germinability at 15$\sp\circ$C and classified as cold germinable (CG) or non-cold germinable (NCG). Accessions meeting the following criteria were classified as CG: germination $>$80%, EI $\leq$ 240, HI $\leq$ 265, and CI $\leq$ 290. EI, HI, and CI are mean hours to emergence, hypocotyl elongation and cotyledon expansion respectively. Only 5% of the accessions examined were considered as CG.

Seedling growth of CG (PI 126156, PI 126197, and 'Persia 202') and NCG ('Delicious 51', 'Minnesota Midget', 'Old Time Tennessee', Russian 4141) muskmelon genotypes was compared. Seedlings were grown to 30$\sp\circ$C to the …

Rowcover Modification Of Carbon And Mineral Nutrient Partitioning In Strawberry (Fragaria Ananassa, Duch), Karen Lynn Brownlee Gast

Doctoral Dissertations

In cool temperature climates where plant growth may be limited by short growing seasons and low temperature stress rowcovers are being used to increase production of fruit and vegetable crops. Two field experiments were conducted to investigate how floating rowcovers applied during autumn, winter and spring affect plant growth and development. The first experiment, 1985-86, examined mineral nutrient and biomass partitioning in a short-day cultivar, 'Sparkle', and a day-neutral cultivar, 'Fern', in rowcovered and nonrowcovered plants in autumn. The second experiment, 1986-87 examined carbon, nitrogen and biomass partitioning over time in autumn and in spring and development of yield components …

Characterization And Application Of Monoclonal Antibody And Bovine Neutrophil Reactivity To Pasteurella Haemolytica Antigens., Frank William Austin

LSU Historical Dissertations and Theses

Monoclonal antibodies (McAbs) were prepared against Pasteurella haemolytica serotype 1 (Ph-1) capsular material to identify, quantitate and purify antigens. McAbs were selected by ELISA and characterized according to their isotype, cross-reactivity with P. haemolytica and P. multocida serotypes in ELISA, antigen formalin sensitivity and ability to cause bacterial agglutination. Four groups of McAbs were established each recognizing a different epitope. Various P. haemolytica and P. multocida serotypes were found to share several epitopes demonstrating their antigenic relatedness. A colorimetric assay, based on tetrazolium dye reduction by bovine neutrophils, was adapted for the measurement and characterization of Ph-1 cytotoxin activity. Using …

Multisensory Discrimination And Representational Memory Deficits In Post-Thiamine Deficient Rats: Testing An Animal Model Of Human Wernicke-Korsakoff's Disease, Russell Laine Knoth

Doctoral Dissertations

The most common cause of diencephaic amnesia in human is Wernicke-Korsakoff's disease, the psychological component of a nutritional polyneuropathy associated with chronic alcoholism. It has long been understood that Wernicke-Korsakoff's disease is caused by thiamine deficiency. The symptoms of the acute Wernicke's phase of this disease include disorientation, ataxia, and ocular nystagmus, and if left untreated, death. If treated with thiamine, the acute symptoms quickly subside. However, following recovery from the acute Wernicke's symptoms, many patients evidence the symptoms of the chronic Korsakoff's syndrome, which includes both global anterograde and retrograde memory deficits and personality changes. The memory deficits observed …

The Systematics Of The Genus Thyanta Stal (Hemiptera:Heteroptera:Pentatomidae)., David Allen Rider

LSU Historical Dissertations and Theses

The pentatomid genus Thyanta Stal is one of several large genera in the nominate subfamily and tribe. Thyanta belongs among those genera of Pentatomini lacking a spine or tubercle at the base of the third (second visible) abdominal sternite. The genus is divided into two subgenera: Phacidium Breddin, containing a single species, T. aeruginosa Berg; and the nominate subgenus, containing 36 species and one subspecies. The subgenus Thyanta is further divided into four species groups based primarily on differences and similarities in male and female genitalia. The perditor species group contains nine species and one subspecies, the maculata species group …

Epidemiology Of Campylobacter Jejuni., Kanagasundaram Yogasundram

LSU Historical Dissertations and Theses

A study was conducted to determine the prevalence of Campylobacter jejuni in various avian species and humans. Cloacal swabs derived from birds submitted to the Louisiana Veterinary Medical Diagnostic Laboratory for necropsy examination during the period February 1987 through July 1988 were routinely cultured for C. jejuni using Butzler's selective medium. Campylobacter jejuni was isolated from 10.1% of the cases examined. The isolation rate was 25.2% in Galliformes, 12.9% in Anseriformes, 8.3% in Columbiformes, 7.7% in Falconiformes, and 0.6% in Psittaciformes. None of the other orders of birds examined yielded C. jejuni. Prevalence data demonstrated that Galliformes are important reservoirs …

Antigenic Analysis Of Equine Infectious Anemia Virus Using Monoclonal Antibodies., Khalid Abdullah Hussain

LSU Historical Dissertations and Theses

Monoclonal antibodies (MCAbs) produced against the prototype cell-adapted Wyoming strain of equine infectious anemia virus (EIAV), a lentivirus, were studied for reactivity with the homologous prototype and 16 heterologous isolates. Eighteen hybridomas producing MCAbs were isolated. Western blot (immunoblot) analyses indicated that 10 were specific for the major envelope glycoprotein (gp90) and 8 for the transmembrane glycoprotein (gp45). Four MCAbs specific to epitopes of gp90 neutralized prototype EIAV infectivity. These neutralizing MCAbs apparently reacted with variable regions of the envelope gp90, as evidenced by their unique reactivity with the panel of isolates, suggesting recognition of at least three different neutralization …

A Study On The Toxicity Of Sesbania Drummondii In Chickens And Rats., Marie-Lorraine Marceau-Day

LSU Historical Dissertations and Theses

A comparative study of two susceptible species, the chicken and the rat, to crude and partially purified extracts of the plant Sesbania drummondii was undertaken. Partial physical and chemical characterization of crude sesbania extracts has been accomplished including temperature and pH stability, molecular weight fractionation and high pressure liquid chromatography and thin layer chromatography retention times. The toxicity of these different fractions could be differentiated with respect to weight loss, mortality, morbidity, serum protein changes and effect on PChE (Pseudocholinesterase) activities. The results indicated that more than one toxin exists in crude extracts of this plant. The pathophysiological findings could …

Effects Of Quantity Of Epicuticular Wax On Leaves And Nitrogen Fertilization Rates On Resistance Of Rice (Oryza Sativa L.) To Sheath Blight (Rhizoctonia Solani Kuhn (Thanatephorus Cucumeris (Frank) Donk);)., Roland Chris Yarkpah Massaquoi

LSU Historical Dissertations and Theses

Nine rice cultivars with different levels of resistance to sheath blight, caused by Rhizoctonia solani, were evaluated in the field and greenhouse for quantity of epicuticular wax (EW) from leaves, infection cushion (IC) formation by the pathogen on leaves, and the relationship of these factors to disease resistance. Comparisons among resistant and susceptible cultivars using scanning electron microscopy suggested that more EW was found on the leaf blade and sheath surfaces of resistant cultivars. Gravimetric analysis of EW from rice leaves supported these observations. EW production at different growth stages increased until the boot stage and then dropped. Correlation coefficients …

Physiological And Behavioral Responses To Aerial Exposure In The Asian Clam, Corbicula Fluminea (Muller)., Roger Anthony Byrne

LSU Historical Dissertations and Theses

Aerially exposed, bivalve molluscs face opposing problems of preventing water loss, and maintaining metabolism. Because of the unpredictability of emersion duration, most freshwater bivalve families are capable of extensive emersion tolerance. Corbicula fluminea (Muller) is a relatively recent invader of freshwater and shares many physiological features with its estuarine ancestors. It might be expected to be intermediate in its emersion responses between those of more ancient freshwater forms, and those of estuarine clams. In air, C. fluminea displayed ventilatory behaviors which were associated with high rates of aerial O$\sb2$ uptake and CO$\sb2$ release. Normoxically exposed clams had bursts of heat …

The Effects Of Temperature Stress On The Bovine Pituitary-Adrenal-Ovarian Axis: An In-Vitro Study., Terry Davis

LSU Historical Dissertations and Theses

The effect of temperature stress on profiles of LH and FSH from pituitary cells; aldosterone, progesterone, cortisol and corticosterone from adrenocortical cells; and estradiol and progesterone from granulosa cells were evaluated using bovine anterior pituitary, adrenocortical and granulosa cells in primary cultures. Cells were grown to confluency in a 37$\sp\circ$C humidified incubator containing 95% O$\sb2$ and 5% CO$\sb2$. Upon reaching confluency, half of the wells were assigned to 40$\sp\circ$C incubation temperature while the other half remained at 37$\sp\circ$C. The 37$\sp\circ$C temperature represented control conditions whereas 40$\sp\circ$C represented heat stress. Various biological substances, that have been reported to alter hormone production, …

Social Organization, Reproductive Behavior, And Zoogeography Of Some Indo-Pacific Hawkfishes (Cirrhitidae)., Terry John Donaldson

LSU Historical Dissertations and Theses

The social organization and reproductive behavior of ten species of hawkfishes was studied at several Pacific localities. In addition, the zoogeography of all Indo-West Pacific cirrhitids was considered in relation to both the Indo-Malayan triangle as a center of species diversity and the isolation of the Pacific and Indian ocean basins during Quaternary events. Patterns of hawkfish distribution and species richness, reflected in high levels of endemism in both the Pacific and Indian ocean basins, support the hypothesis that the Indo-Malayan triangle is not so much a center of speciation as one of the confluence of two distinct centers 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 …

The Effects Of Fire On Forest Community Composition, Structure, And Pattern In Florida Sandhills., Alan John Rebertus

LSU Historical Dissertations and Theses

The influence of fire on turkey oak (Quercus laevis Walt.) and sand live oak (Q. geminata Small) populations was examined in experimental fires in sandhills near Tampa. Turkey oak crown survival was positively related to oak dbh, distance to the nearest longleaf pine (Pinus palustris Mill.), and dbh of the nearest pine. The pyrogenic litter of pines adversely affected survival of small turkey oaks within 10-20 m of the nearest pine, depending on fire severity. Resprouting of crown-killed turkey oaks was inversely related to oak dbh and, in one field, distance to the nearest pine. Poor resprouting away from pines …

Biochemical And Physiological Mechanisms Involved In Insecticide Toxicity And Host Plant Resistance To The Soybean Looper, Pseudoplusia Includens (Walker)., Randy Lynn Rose

LSU Historical Dissertations and Theses

Permethrin, fenvalerate, methomyl, acephate and methyl parathion were bioassayed on larvae of the soybean looper, Pseudoplusia includens (Walker) and the velvetbean caterpillar, Anticarsia gemmatalis (Hubner) fed on susceptible (Bragg) versus resistant (PI 227687) soybean, Glycine max (L.) Merr., cultivars. Soybean loopers reared on resistant leaves were significantly more susceptible to acephate (2-fold) than when reared on susceptible leaves. Velvetbean caterpillars fed resistant leaves were more susceptible to both fenvalerate (1.5-fold) and acephate (1.6-fold) than when fed susceptible leaves. Differences in toxicity of other insecticides due to host plant were not observed. Midgut homogenates from last instar soybean loopers reared on …

Cell Division Studies Of Escherichia Coli: Expression And Protein Localization Of Cell Septation Gene, Ftsa., Chong Chon Younghae

LSU Historical Dissertations and Theses

FtsA is a gene essential for cell septation. It has been postulated to have both regulatory and structural functions. To study the structural involvement of the FtsA protein in septum formation, four FtsA-LacZ protein fusions were constructed using a mini-Mu transposon (MudII1734). When maxicells containing either ftsA-lacZ or ftsA specifying plasmids were radioactively labelled and fractionated, FtsA-LacZ fusion protein and FtsA were located in both the membrane and cytoplasmic fractions. The FtsA-LacZ fusion proteins were also located in dividing wild type dividing cells by measuring $\beta$-galactosidase activity. Cell envelope fractions from a sucrose equilibrium gradient had $\beta$-galactosidase activity in outer …

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 …