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The Uptake And Distribution Of Diethyltoluenediamine In The Male Sprague Dawley Rat., Michael Charles Babin Jan 1997

The Uptake And Distribution Of Diethyltoluenediamine In The Male Sprague Dawley Rat., Michael Charles Babin

LSU Historical Dissertations and Theses

Diethyltoluenediamine (CAS 68479-98-1) is a ring-ethylated analog of toluenediamine (TDA) and like TDA, consists of the 2,4- and 2,6-diamine isomers. DETDA was developed by Albermarle Corporation as a substitute for TDA in some applications. To determine the uptake and distribution of 2,4- and 2,6-DETDA, 5 groups of 4 adult male Sprague Dawley rats were gavaged at 179 $\mu$mol/kg body weight with ($\sp3$H) -2,4- or ($\sp3$H) -2,6-DETDA. Multiple tissues were collected at 1, 4, 8, 24 and 48 hours. Very high levels of label occurred in the gastrointestinal system and bladder during the first 8 hours while liver and kidney exhibited …

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Flight Muscle Histolysis In The Female House Cricket, Acheta Domesticus., Rush Hoyet Oliver Jan 1997

Flight Muscle Histolysis In The Female House Cricket, Acheta Domesticus., Rush Hoyet Oliver

LSU Historical Dissertations and Theses

Flight muscle histolysis was investigated in the dorsal longitudinal muscles (DLMs) of the cricket. Histolysis in the DLMs was characterized by analysis of total protein content, tissue wet weight, and relative percent muscle shortening. Initial declines of total protein indicated the JH signal initiating histolysis occurred by Day 2. Histolysis was essentially complete by Day 3. Ligation of Day 1 crickets prevented histolysis but this inhibition could be prevented by continual topical treatments with methoprene. Ligation of Day 2 crickets did not prevent histolysis. A requirement for active protein expression was demonstrated by analysis of synthesis block by cycloheximide and …

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Yellagonga Wetlands: A Study Of The Water Chemistry And Aquatic Fauna, Adrianne Kinnear, Patrick Garnett, Hugo Bekle, K. Upton Jan 1997

Yellagonga Wetlands: A Study Of The Water Chemistry And Aquatic Fauna, Adrianne Kinnear, Patrick Garnett, Hugo Bekle, K. Upton

Research outputs pre 2011

Wetlands worldwide are continually threatened by urbanisation and Western Australia is no exception. Since European settlement in 1829, it has been estimated that at least 75% of the wetlands of the Swan Coastal Plain have disappeared (Halse, 1988). The remaining 25% continue to be threatened by eutrophication and pollution, changes in hydrology and water level patterns, clearing of riparian vegetation, aesthetic disruption and weed invasion (CALM, 1980; Davis and Rolls, 1987; Wrigley et al., 1991; Balla and Davis, 1995). These degradation components are interrelated and largely the consequence of the extensive removal of surrounding vegetation...

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Genetics And Functions Of Herpes Simplex Virus Type 1 (Hsv-1) Glycoprotein K (Gk) In Virus Envelopment And Egress., Sukhanya Jayachandra Jan 1997

Genetics And Functions Of Herpes Simplex Virus Type 1 (Hsv-1) Glycoprotein K (Gk) In Virus Envelopment And Egress., Sukhanya Jayachandra

LSU Historical Dissertations and Theses

HSV-1(KOS)$\Delta$gK, a virus lacking the UL53 gene coding for glycoprotein K(gK) was constructed, characterized and compared to the partially deleted gK-null virus HSV-1(F)-gK$\beta$. $\Delta$gK and F-gK$\beta$ viruses produced microscopic plaques on Vero cells at 48 hours post infection. F-gK$\beta$ plaques at 72 hours post infection contained fused cells (syn), while $\Delta$gK plaques resembled wild-type KOS plaques ($syn\sp+$). $\Delta$gK replicated efficiently in exponentially dividing Vero cells whereas F-gK$\beta$ yields were 10 and 1000-fold lower than $\Delta$gK yields in HEp-2 or log-phase Vero cells, respectively. Electron micrographs of $\Delta$gK-infected Vero cells revealed large numbers of capsids in the nuclei of Vero, but …

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Cloning, Sequencing And Regulation Of The Rhodobacter Capsulatus Hemh Gene., Ekaterina Vladislavova Kanazireva Jan 1997

Cloning, Sequencing And Regulation Of The Rhodobacter Capsulatus Hemh Gene., Ekaterina Vladislavova Kanazireva

LSU Historical Dissertations and Theses

Rhodobacter capsulatus, a purple non-sulfur photosynthetic bacterium, synthesizes four tetrapyrrole end products: heme, bacteriochlorophyll, siroheme and vitamin B$\sb{12}$ via the common tetrapyrrole biosynthetic pathway. The biosynthesis of tetrapyrroles in R. capsulatus is a complex and precisely controlled process which has been under extensive investigation. In order to study the regulation of tetrapyrrole biosynthesis, the R. capsulatus hemH gene was cloned by complementation of an E. coli $\Delta hemH$ mutant and sequenced. The enzyme ferrochelatase, encoded by the hemH gene, catalyzes the insertion of ferrous iron into protoporphyrin IX, thus producing heme. The consensus ferrochelatase signature sequence was found in the …

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Development And In Vivo Evaluation Of A Pura Mutant Strain Of The Channel Catfish Pathogen Edwardsiella Ictaluri., Mark Lee Lawrence Jan 1997

Development And In Vivo Evaluation Of A Pura Mutant Strain Of The Channel Catfish Pathogen Edwardsiella Ictaluri., Mark Lee Lawrence

LSU Historical Dissertations and Theses

Edwardsiella ictaluri is the causative agent of enteric septicemia of catfish (ESC), which is the most serious disease affecting the channel catfish industry. Killed vaccines have been inconsistent in providing protection against ESC, and no live attenuated vaccines have been described. The purpose of this study was to develop a nutritionally attenuated mutant strain of E. ictaluri and evaluate its virulence and vaccine efficacy. An E. ictaluri genomic library was constructed, and a clone containing the purA gene was isolated and sequenced. The E. ictaluri purA gene was found to have several features in common with the E. coli purA …

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Caprine Sperm Cells As Vectors For Gene Transfer., Yongxin Sun Jan 1997

Caprine Sperm Cells As Vectors For Gene Transfer., Yongxin Sun

LSU Historical Dissertations and Theses

Goat sperm cells were used as a model to evaluate sperm-mediated gene transfer. Fresh and frozen-thawed goat sperm cells were co-incubated with radio-labelled foreign DNA. After 10 extensive washings, the compacted sperm retained foreign DNA. Confocal microscopy confirmed that the position on the sperm cell responsible for binding of foreign DNA was located in both the anterior and the posterior heads of caprine sperm cells. Furthermore, confocal longitudinal sections of the sperm cells showed that foreign DNA had penetrated into goat sperm nuclei. In this study, 37% of the fresh goat sperm and 33% of the frozen-thawed goat sperm cells …

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Relative Rates Of Molecular Evolution In Rodents And Their Symbionts., Theresa Ann Spradling Jan 1997

Relative Rates Of Molecular Evolution In Rodents And Their Symbionts., Theresa Ann Spradling

LSU Historical Dissertations and Theses

The focus of this dissertation is the relative tempo of molecular evolution among organisms of varying levels of relatedness. Because this is a rapidly expanding area of research, Chapter 1 is devoted to a review of the current state of knowledge on rates of molecular evolution. In Chapter 2, I present an analysis of relative rates of evolution among several distantly related rodents. The heterogeneity in rate of evolution of the cytochrome b gene observed here cannot be explained by metabolic rate, body size, generation time, or nucleotide-generation time. Likewise, there is no evidence that these differences in rate of …

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Cloning And Expression Of Capsid Proteins Of Hepatitis A Virus In Escherichia Coli., Lingaiah Chandrashekar Jan 1997

Cloning And Expression Of Capsid Proteins Of Hepatitis A Virus In Escherichia Coli., Lingaiah Chandrashekar

LSU Historical Dissertations and Theses

Hepatitis A virus (HAV), the causative agent of food and water borne acute hepatitis worldwide, is very difficult and expensive to propagate in tissue culture. Large scale production of HAV proteins in E. coli by recombinant DNA techniques would be invaluable for antisera production, biochemical analyses and in developing sensitive diagnostic tests. Therefore, PCR amplified DNA fragments encoding the HAV capsid proteins were cloned individually into prokaryotic expression vectors for production of either recombinant fusion or non-fusion proteins. Cloning and expression of HAV capsid genes, which induced toxic effects in certain host E. coli, was tolerated better by protease-deficient host …

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Pest Status And Management Of Beet Armyworm, Spodoptera Exigua (Hubner), On Cotton In Louisiana., Victor James Mascarenhas Jan 1997

Pest Status And Management Of Beet Armyworm, Spodoptera Exigua (Hubner), On Cotton In Louisiana., Victor James Mascarenhas

LSU Historical Dissertations and Theses

Field cage studies were conducted to measure the effects of late season beet armyworm, Spodoptera exigua (Hubner), infestations (0, 1, 3, and 6 egg masses per 5.1 row m) on defoliation, fruit damage, and yield of cotton. Light penetration through the canopy was significantly higher in infested plots. Although a trend for increased numbers of damaged fruiting forms with increases in egg mass density was observed, there were no significant differences between infested and control plots. There were no significant differences in the cumulative number of shed fruiting forms or yield between infested and control plots. Field tests were conducted …

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Metamorphosis Of The Hawaiian Stream Goby Sicyopterus Stimpsoni: A Structural, Functional, And Behavioral Analysis., Heiko Lars Schoenfuss Jan 1997

Metamorphosis Of The Hawaiian Stream Goby Sicyopterus Stimpsoni: A Structural, Functional, And Behavioral Analysis., Heiko Lars Schoenfuss

LSU Historical Dissertations and Theses

The endemic goby Sicyopterus stimpsoni is unique among five species of Hawaiian freshwater fishes because it undergoes rapid metamorphosis of cranial structures during postlarval development. These fishes are amphidromous and return after a prolonged stay in the ocean to streams where they are confined to estuaries until completion of cranial restructuring. Within 48 hours after entering fresh water, head width increases significantly, while total length and head length remains unchanged. Weight decreases by approximately 15% during this period. The upper lip enlarges greatly, and the mouth position shifts from terminal to nearly ventral. Shape analysis of radiographs taken from a …

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Aerenchyma Development In The Freshwater Marsh Species Sagittaria Lancifolia L., Elisabeth Ellen Schussler Jan 1997

Aerenchyma Development In The Freshwater Marsh Species Sagittaria Lancifolia L., Elisabeth Ellen Schussler

LSU Historical Dissertations and Theses

Aerenchyma tissue consists of gas channels that provide a pathway for O$\sb2$ transport to waterlogged roots. Aerenchyma gas spaces are formed by cell separation or cell lysis during development. Light microscopy was used to determine how aerenchyma develops in Sagittaria lancifolia, a freshwater marsh species, when plants were grown in hydroponic solution. Petiole aerenchyma was formed by cell separation caused by differential cell expansion and division. In the root cortex, certain radial files of cells separated slightly from adjacent files and then lysed to form gas spaces. Development of root aerenchyma was characterized in S. lancifolia, Zea mays, and Oryza …

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Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones Jan 1997

Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones

Vanderbilt Law School Faculty Publications

As first year law students unhappily discover, the meaning of "law" is frustratingly protean, shifting by usage and user. Depending on whom you ask, law is a system of rules, a body of precedents, a legislative enactment, a collection of norms, a process by which social goals are pursued, or some dynamic mixture of these. Law's principal purpose is to define and protect individual rights, to ensure public order, to resolve disputes, to redistribute wealth, to dispense justice, to prevent or compensate for injury, to optimize economic efficiency, or perhaps to do something else. And yet one thing is irreducibly …

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The Effects Of Adrenergic And Cholinergic Stimulation On Skin Gland Secretions In The Dwarf African Frog Hymenochirus Curtipes, Daniel H. Gong Jan 1997

The Effects Of Adrenergic And Cholinergic Stimulation On Skin Gland Secretions In The Dwarf African Frog Hymenochirus Curtipes, Daniel H. Gong

University of the Pacific Theses and Dissertations

Many studies have been done on the neural control of serous gland secretion in the skin of frogs and newts. However, no studies have been published on the effects of adrenergic and cholinergic neurotransmitters on the sexually dimorphic breeding glands of male frogs. The present study examined the effects of neurotransmitters on the serous and breeding glands of Hymenochirus curtipes. Explants of dorsal skin and postaxial skin (containing whole breeding glands) were incubated in vitro with epinephrine, norepinephrine or acetylcholine for 30 minutes. The explants were then preserved and examined histologically for signs of secretion. The area and perimeter of …

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Rickettsia Felis, A Newly Discovered Rickettsia Associated With The Cat Flea (Ctenocephalides Felis Bouche)., Jimmy Wedincamp Jr Jan 1997

Rickettsia Felis, A Newly Discovered Rickettsia Associated With The Cat Flea (Ctenocephalides Felis Bouche)., Jimmy Wedincamp Jr

LSU Historical Dissertations and Theses

A study was performed to determine the life cycle of Rickettsia felis, a novel bacterium associated with cat fleas (Ctenocephalides felis Bouche). Cat flea populations maintain R. felis in successive generations by efficient transovarial transmission. Transovarial transmission was demonstrated in our study up to 12 generations. The mean infection rate for the progeny of fleas maintained on both cats and an artificial membrane system were comparable (64.3% and 58% respectively). Cats with no prior exposure to fleas were exposed to fleas infected with Rickettsia felis and monitored monthly for seroconversion via IFA. Blood samples were assayed for the presence of …

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The Polysaccharide Capsule Of Vibrio Vulnificus: Virulence, Transposon Mutagenesis, And The Identification Of An Essential Gene., Amy Buscher Zuppardo Jan 1997

The Polysaccharide Capsule Of Vibrio Vulnificus: Virulence, Transposon Mutagenesis, And The Identification Of An Essential Gene., Amy Buscher Zuppardo

LSU Historical Dissertations and Theses

The extracellular capsule polysaccharide (CPS) of Vibrio vulnificus is a primary virulence factor which allows survival of the bacteria in the human host. To study the genes involved in the production of the polysaccharide capsule, 23 mutants were generated that lost their ability to produce CPS due to the insertion of a mini-transposon into the genome of the encapsulated clinical strain V. vulnificus 1003 (O). The mutants were examined by Southern blot analysis to ensure the transposon had inserted only once in the chromosome. Exoenzymes, which are believed to contribute to the virulence of the organism, produced by all 23 …

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The Radioresistance Of Deinococcus Radiodurans., Valerie Mattimore Jan 1997

The Radioresistance Of Deinococcus Radiodurans., Valerie Mattimore

LSU Historical Dissertations and Theses

Deinococcus radiodurans is a remarkably ionizing radiation resistant bacterium. As a vegetative cell it is capable of withstanding 5,000 Gy ionizing radiation without evidence of death or mutation. D. radiodurans survives irradiation by repairing DNA damage via an extremely efficient DNA repair system. However, this DNA repair system has not been completely defined. In addition, the selective process allowing the evolution of high level radioresistance has remained a question. This dissertation bolsters the understanding of the DNA repair system of D. radiodurans by characterizing a collection of ionizing radiation sensitive (IRS) mutants. The level of radioresistance is quantified and transformation …

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Biology: What One Needs To Know, Ursula Goodenough Dec 1996

Biology: What One Needs To Know, Ursula Goodenough

Biology Faculty Research

Biology on this planet represents an astonishing experiment in carbon-based chemistry which, over billions of years, has generated billions of species adapted to countless major and minor fluctuations in ecological circumstances. In one sense there is no way to generalize about biology. While biological activities can all be ultimately explained by physical laws (like everything else in the universe), it is the emergent intensely particular properties of organisms that most interest us. This essay represents an attempt to describe some of the more prominent patterns that emerge from the sea of biological particularities, patterns that present many opportunities for religious …

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Modeling Interactions Of Browsing Predation, Infaunal Activity And Recruitment In Marine Soft-Sediment Habitats, Sara M. Lindsay, David S. Wethey, Sarah A. Woodin Oct 1996

Modeling Interactions Of Browsing Predation, Infaunal Activity And Recruitment In Marine Soft-Sediment Habitats, Sara M. Lindsay, David S. Wethey, Sarah A. Woodin

Faculty Publications

In marine soft-sediment habitats, the sediment surface is altered by activities of sediment dwellers (infauna). Such biogenic disturbance can influence recruitment success if settling larvae and juveniles avoid disturbed sites or if juveniles die as a result of disturbance after settling. Because infauna commonly lose exposed body parts to browsing predators and disturb less sediment as a result, we developed a simulation model to examine the interactions between browsing predation, infaunal adult activity, and recruitment. Sediment disturbance in the model was based on data for the polychaete Abarenicola pacifica. We simulated the activity of two general types of predators: prey …

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Characterization Of An Octopamine Receptor Gene In Drosophila Melanogaster., Kelley Lynn Colvin Aug 1996

Characterization Of An Octopamine Receptor Gene In Drosophila Melanogaster., Kelley Lynn Colvin

Student Work

The biogenic amine octopamine is a versatile signaling molecule that acts in essential physiological functions in invertebrates. Its roles in neurotransmission, neurohormone regulation and neuromodulation are achieved through interaction with G-protein coupled receptors. Such invertebrate receptors are structurally and functionally analogous to vertebrate adrenergic receptors. A human brain β2-adrenergic receptor cDNA clone was used as a hybridization probe to identify a Drosophila gene encoding an octopamine/tyramine receptor. This 367 base pair fragment of Drosophila genomic DNA, homologous to the putative sixth and seventh transmembrane regions of adrenergic receptors, was used to isolate an octopamine/tyramine receptor 3.3 Kb cDNA clone from …

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1: "To Know Ourselves", The U.S. Department Of Energy, The Human Genome Project Jul 1996

1: "To Know Ourselves", The U.S. Department Of Energy, The Human Genome Project

Genomics: Past & Future

AT THE END OF THE ROAD in Little Cottonwood Canyon, near Salt Lake City, Alta is a place of near-mythic renown among skiers. In time it may well assume similar status among molecular geneticists. In December 1984, a conference there, co-sponsored by the U.S. Department of Energy, pondered a single question: Does modern DNA research offer a way of detecting tiny genetic mutations—and, in particular, of observing any increase in the mutation rate among the survivors of the Hiroshima and Nagasaki bombings and their descendants? In short the answer was, Not yet. But in an atmosphere of rare intellectual fertility, …

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Settlement And Early Post-Settlement Survival Of Sessile Marine Invertebrates On Topographically Complex Surfaces: The Importance Of Refuge Dimensions And Adult Morphology, Linda J. Walters, David S. Wethey Jun 1996

Settlement And Early Post-Settlement Survival Of Sessile Marine Invertebrates On Topographically Complex Surfaces: The Importance Of Refuge Dimensions And Adult Morphology, Linda J. Walters, David S. Wethey

Faculty Publications

We predicted that both refuge dimension and growth form would influence settlement and short-term post-settlement success (≤7 d) of sessile marine invertebrates that live attached to hard substrata in low energy environments. Individuals with unlimited attachment to the substrata should rapidly be protected by their growth form, thus decreasing their need to settle in refuges and limiting the length of time any locations on heterogeneous substrata act as refuges. Alternatively, organisms with limited attachment to the substrata should remain susceptible to the causes of mortality for a longer time, and as a result should settle in high quality refuges (sites …

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Abundant Protein-Containing Particles In The Sea, Richard A. Long, Farooq Azam Jun 1996

Abundant Protein-Containing Particles In The Sea, Richard A. Long, Farooq Azam

Faculty Publications

The interaction of bacteria with particulate organic matter has implications for organic matter cycling and bacterial ecology in the ocean. Until recently, the focus has been on 'classical' particles visible by unaided eye (marine snow) or light microscopy. Recent discoveries of several new types of abundant particles, from sub-micrometer to sub-marine snow, are changing our ideas of the physical and chemical nature of the particle field with which pelagic bacteria interact. Previous workers have discovered polysaccharide-containing (Alcian Blue stainable) transparent exopolymer particles (TEP) ranging from 3 to 100s of micrometers. Looking for additional components of the sub-marine snow particle field, …

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A Molecular Analysis Of An Octopamine Receptor Gene In Drosophila Melanogaster., Pramodini Purushottam Rode May 1996

A Molecular Analysis Of An Octopamine Receptor Gene In Drosophila Melanogaster., Pramodini Purushottam Rode

Student Work

Octopamine is a biogenic amine. It plays an important role as neurohormone neuromodulator and neurotransmitter in Drosophila melanogaster. These physiological functions of octopamine are essential in feeding, mating and fight-or-flight behavior. Octopamine receptors are structurally and fundamentally similar to the vertebrate adrenergic receptors. A Drosophila gene encoding an octopamine/tyramine receptor was previously identified by probing a Drosophila genomic library with a human brain β2 adrenergic receptor cDNA clone. After identifying a 367-bp fragment of a Drosophila genomic DNA, a cDNA library prepared from head mRNA was screened and a 3.3 kb cDNA, containing the inferred protein coding region of the …

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Properties And Regulation Of The Calcium Ion Pump In Heart And Skeletal Muscle Sarcoplasmic Reticulum, Cynthia Elaine Hawkins Jan 1996

Properties And Regulation Of The Calcium Ion Pump In Heart And Skeletal Muscle Sarcoplasmic Reticulum, Cynthia Elaine Hawkins

Digitized Theses

In heart and skeletal muscle, the sarcoplasmic reticulum (SR) plays a critical role in the contraction-relaxation cycle of the myocyte: a Ca{dollar}\sp{lcub}2+{rcub}{dollar} channel releases Ca{dollar}\sp{lcub}2+{rcub}{dollar} from SR into cytoplasm to trigger contraction, and a Ca{dollar}\sp{lcub}2+{rcub}{dollar} pump resequesters Ca{dollar}\sp{lcub}2+{rcub}{dollar} to cause relaxation. A major regulator of this cycle is {dollar}\rm Ca\sp{lcub}2+{rcub}{dollar}/calmodulin-dependent protein kinase (CaM kinase), which is known to phosphorylate and thereby activate the cardiac SR Ca{dollar}\sp{lcub}2+{rcub}{dollar} pump, Ca{dollar}\sp{lcub}2+{rcub}{dollar} channel and endogenous Ca{dollar}\sp{lcub}2+{rcub}{dollar}-pump inhibitor phospholamban. This thesis examines the Ca{dollar}\sp{lcub}2+{rcub}{dollar} pump and its regulation in different tissues (cardiac, slow-twitch and fast-twitch muscle SR: CMSR, SMSR and FMSR) and different stages in …

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Some Physiological Effects Of Stress In The American Cockroach Periplaneta Americana (L), Shigui Liu Jan 1996

Some Physiological Effects Of Stress In The American Cockroach Periplaneta Americana (L), Shigui Liu

Digitized Theses

The effects of different forms of stress on the American cockroach, Periplaneta americana (L.) have been systematically examined. This study demonstrated that at least two stress-related events occurred in the haemolymph of the American cockroach. First, the data clearly indicated that a large increase in hypertrehalosemic hormones occurred in the haemolymph of stressed cockroaches. Secondly, proteolytic activity in the haemolymph of stressed cockroaches was greatly increased. The increase of both hypertrehalosemic hormones and proteolytic activity in the haemolymph appeared to be a non-specific response to different forms of stress, including chemical poisoning with lindane, immobilization, forced movement, starvation, and elevated …

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Limbic Mechanisms Controlling Arterial Pressure, Stefanie Roder Jan 1996

Limbic Mechanisms Controlling Arterial Pressure, Stefanie Roder

Digitized Theses

Three series of experiments were done to investigate the output pathways from the central nucleus of the amygdala (ACe) involved in the control of arterial pressure. The first series of experiments provided the first demonstration that the arterial pressure responses elicited during stimulation of ACe were mediated via a direct pathway to the bed nucleus of the stria terminalis (BST). Microinjection of retrograde tract tracers into depressor regions of BST resulted in labelled neurons within predominantly the lateral subdivision of ACe. In addition, iontophoresis of the anterograde tract tracer PHA-L into cardiovascular responsive regions of ACe resulted in fiber and …

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Expression Of Sodium Pump Subunit Genes During Mouse Preimplantation Development, Daniel James Macphee Jan 1996

Expression Of Sodium Pump Subunit Genes During Mouse Preimplantation Development, Daniel James Macphee

Digitized Theses

The Na,K-ATPase or sodium pump is an enzyme that is found in most animal cells. The enzyme pumps sodium and potassium ions against their concentration gradients and is hypothesized to be a mediator of fluid accumulation during mouse preimplantation development. The purpose of the present study was to determine, using reverse transcriptase-polymerase chain reaction (RT-PCR), whether all {dollar}\alpha\ (\alpha1,\ \alpha2,\ \alpha3,\ \alpha4{dollar}) and {dollar}\beta\ (\beta1{dollar} and {dollar}\beta{dollar}2) isoforms of the sodium pump were expressed during preimplantation development. Previous work by Watson and Kidder (1988) had shown that the {dollar}\alpha{dollar} subunit was localized to the basolateral domains of mural trophectoderm surrounding …

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Male Reproductive Success And The Mating System Of Bushy-Tailed Woodrats, Michael Graham Topping Jan 1996

Male Reproductive Success And The Mating System Of Bushy-Tailed Woodrats, Michael Graham Topping

Digitized Theses

Bushy-tailed woodrats are nocturnal cricetid rodents distributed throughout the mountainous regions of western North America. Despite a number of studies on the population ecology of this species, little is known about the behaviour of males during the breeding season.;I investigated the reproductive behaviour of male bushy-tailed woodrats in three ways. First, I examined the spatial distribution of individuals within a breeding population, using radiotelemetry and mark-recapture livetrapping. Both males and females exhibited considerable overlap with animals of both sexes, mean intersexual and intrasexual overlap values for each sex did not differ in two of the three years of study. This …

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The Central Serotonergic And Cholinergic Systems As Activators Of The Electrocorticogram And Behavior, Hans Christian Dringenberg Jan 1996

The Central Serotonergic And Cholinergic Systems As Activators Of The Electrocorticogram And Behavior, Hans Christian Dringenberg

Digitized Theses

Experiments were performed on the role of ascending cholinergic and serotonergic electrocortical activating systems and their role in normal physiology and behavior. In urethane-anesthetized rats, electrocortical activation could be obtained by electrical stimulation of the amygdala, the dorsal raphe, the locus coeruleus area, the superior colliculus, and the orbitofrontal cortex. Activation elicited from the amygdala, the locus coeruleus area, and most orbitofrontal sites was abolished by systemic administration of the cholinergic-muscarinic antagonists scopolamine or atropine. Activation elicited from the dorsal raphe or superior colliculus was largely resistant to anti-muscarinic treatment but was abolished by methiothepin, a serotonergic antagonist. Infusions of …

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