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Regulation Of Ethylene Receptor Expression In Arabidopsis, Xue-Chu Zhao

Doctoral Dissertations

The ethylene receptor family of Arabidopsis consists of five members, ETR1, ETR2, ERS1, ERS2, and EIN4. Regulation of ethylene receptor expression in Arabidopsis was studied using three different approaches. First, the effect of ethylene-pathway mutations upon expression of ETR1 was examined. Ethylene-insensitive mutations in ETR1 resulted in a post-transcriptional increase in levels of the mutant receptor. Treatment of seedlings with silver, which leads to ethylene insensitivity, also resulted in an increase in levels of ETR1. Mutations in other components of the ethylene pathway had little effect upon expression of ETR1. Second, microarray analysis was performed using reciprocal mutants to examine …

Life History Dynamics Of Nudibranch Sibling Species In The Genus Dendronotus In The Gulf Of Maine, Chad Gordon Sisson

Doctoral Dissertations

Two different larval types have been described for the nudibranch Dendronotus frondosus (Ascanius, 1774) in the Gulf of Maine. A taxonomic review of adults with planktrophic larvae and those with lecithotrophic larvae revealed regular differences in radula morphology, and no predictable differences in the reproductive system. These data and previous data on a behavioral reproductive isolation mechanism suggest a new species designation for populations of Dendronotus with lecithotrophic larvae. Laboratory studies were used to compare the larval dispersal potential of the two types of Dendronotus. D. frondosus planktotrophic larvae had a potential planktonic period of approximately 11 weeks at 10°C …

Ec02-174 Leafy Spurge, Robert A. Masters, Brady F. Kappler

University of Nebraska-Lincoln Extension: Historical Materials

Leafy spurge is an invasive weed that infests over three million acres in the northern Great Plains and the prairie provinces of Canada. It is commonly found in rangelands, pastures, roadsides, rights-of-way, and woodlands. Leafy spurge can reduce rangeland and pasture carrying capacity by as much as 75 percent because it competes with forages and cattle avoid grazing areas infested with this weed. In North Dakota where leafy spurge infests about 900,000 acres, estimates of direct and indirect losses exceed $100 million each year. In Nebraska, the direct loss in forage value attributed to leafy spurge has been estimated at …

Ec02-174 Noxious Weeds Of Nebraska: Leafy Spurge, Robert A. Masters, Brady Kappler

University of Nebraska-Lincoln Extension: Historical Materials

Leafy spurge is an invasive weed that infests over three million acres in the northern Great Plains and the prairie provinces of Canada. It is commonly found in rangelands, pastures, roadsides, rights-of-way, and woodlands. Leafy spurge can reduce rangeland and pasture carrying capacity by as much as 75 percent because it competes with forages and cattle avoid grazing areas infested with this weed.

This Extension Circular discusses the biology, identification, distribution and control of leafy spurge.

A Test Of The Ideal Free Distribution In Panhandling Humans, Leann Louise Milinder

Doctoral Dissertations

The Ideal Free Distribution (Fretwell and Lucas, 1970), an optimization model from behavioral ecology, predicts that a group of animals will distribute themselves across habitats with unequal resources such that all animals have equal success rates. The six experiments of this dissertation demonstrated that humans conform to the IFD with about the same sensitivity as animals and respond similarly when assumptions of the model are violated. The present study also revealed that cooperation, and its effect on the functional size of the foraging unit, may be an important factor in understanding the distribution of social foragers.

Experiments 1 and 2 …

Transgenic Manipulation Of Polyamine Metabolism In Poplar, Pratiksha Bhatnagar

Doctoral Dissertations

Polyamines are low molecular weight polycations found in all living organisms. They are involved in plant stress response and development. The study was aimed at analyzing the effects of altered polyamine metabolism on the polyamine and related pathways in transformed poplar cells overexpressing a mouse odc cDNA under the control of 2X 35S CaMV promoter. The transgenic cells (line 2E) showed elevated levels of mouse ornithine decarboxylase enzyme activity, several fold higher amounts of putrescine, a small increase in spermidine, and a small reduction in spermine as compared with non-transgenic (NT) cells. The conversion of labeled ornithine into putrescine was …

Genetic Diversity Of Balbiani Ring L Gene In Two Species Of Chironomus, Lola-Mae Palmer

Seton Hall University Dissertations and Theses (ETDs)

Differences in genetic composition have been predicted among aquatic midge fly larva called chironomids. Although several genes including microsatellites and ribosomal protein genes have been explored in our lab, the gene that has so far been studied the most is the Balbiani Ring (BR) 1 gene. There are several genes in this family, including Balbiani Ring 2.1, 2.2 and 6. These BR genes are known to contain long arrays of tandemly repeated units with a ranked repeat organization (Paulsson et al.1992). This secretory protein gene forms a large puff located on polytene chromosome IV (Bentivegna et al., 1993). The gene …

Age Structure, Species Composition And Succession In A Loess Hills Woodland., Peter Christian Phillips

Student Work

The Loess Hills of central North America is a unique geologic region that historically was dominated by prairie with scattered oak trees in an environment of frequent fires. Following European settlement, woody-plant cover expanded throughout the Loess Hills so that today, existing prairies occur as remnants surrounded by an oak-dominated woodland. Large-, intermediate-, and small-sized trees were sampled along three adjacent lowland-to-upland belt-transects in western Iowa to document more accurately the dynamics of this woody expansion. Trees were cored or cross-sectioned and dated using standard dendrochronological techniques. Results characterize the pre-1850 woody canopy as consisting of a few widely scattered …

The Wooster Voice (Wooster, Oh), 2001-11-08, Wooster Voice Editors

The Voice: 2001-2011

The college sets a goal of $8 million for the new Bornhuetter Hall. The issue includes a draft design of the dorm building. After the events of September 11th, federal authorities slow Wooster's recruitment of international students. Paul Ewald, professor of biology at Amherst College and noted disease expert, visits Wooster to speak on the wide scope of infectious disease and new findings in the field. A piece details information about the different small house on campus and the students that live in them. Additionally, the edition includes a music review of artist Tori Amos's cover album "Strange Little Girls."

Realities Of Rape: Of Science And Politics, Causes And Meanings, Owen D. Jones

Vanderbilt Law School Faculty Publications

This review essay discusses the book A Natural History of Rape: Biological Bases of Sexual Coercion, by Randy Thornhill and Craig Palmer (MIT Press, 2000). The essay builds on work previously appearing in Owen D. Jones, Sex, Culture, and the Biology of Rape: Toward Explanation and Prevention, 87 Cal. L. Rev. 827 (1999) and Owen D. Jones, Law and the Biology of Rape: Reflections on Transitions, 11 Hastings Women's Law Journal 151 (2000).

Abstracts Of Papers, 79th Annual Meeting Of The Virginia Academy Of Science, May 22-25, 2001, James Madison University, Harrisonburg, Virginia

Virginia Journal of Science

Abstracts of papers that were presented at the 79th Annual Meeting of the Virginia Academy of Science, May 22-25, 2001, James Madison University, Harrisonburg, Virginia.

Fisheries Research Report No.128 - Aquaculture And Related Biological Attributes Of Abalone Species In Australia - A Review., Kylie A. Freeman

Fisheries Research Reports

China and Taiwan are the major producers of cultured abalone; with annual production estimated at 3,500 and 3,000 tonnes respectively. The world production of cultured abalone sold in 1999 was 7,775 tonnes. Australian farm production was still relatively low (89 tonne in 1999) but numerous abalone farms have been proposed and many have been constructed. On a national scale, Tasmania and South Australia are the major states involved in temperate abalone culture; however, new projects have commenced in Victoria and considerable interest exists in New South Wales. Pilot scale trials with tropical abalone aquaculture using the Donkey-ear abalone (Haliotis asinina) …

Icam-1 Transmembrane Signaling: Involvement Of Taxreb107 In Icam-1-Mediated Signal Transduction, Brian Lee

Yale Medicine Thesis Digital Library

The role of membrane ICAM-1 in intercellular adhesion, through interaction with the leukocyte beta2 integrin receptors LFA-1 and Mac-1, is well established. However, until recently, ICAM-1 was widely regarded as being simply an "anchor" molecule, promoting, for example, firm adhesion of lymphocytes to vascular endothelial cells. The demonstration that ICAM-1 is connected to the actin-based cytoskeleton through interactions with subcortical actin-binding proteins, such as alpha-actinin, enhanced this concept. However, ICAM-1 has been increasingly shown to have signaling properties of its own. Engagement of ICAM-1 extracellularly, either through its natural counter-receptors, LFA-1/Mac-1, or through antibody mediated clustering, can produce numerous changes …

Pathobiology Of Streptococcus Iniae Infections In Cultured Tilapia., Alvin Cyril Camus

LSU Historical Dissertations and Theses

Streptococcus iniae was first isolated in 1972 from an Amazon River dolphin. It reappeared as a fish pathogen in Japan several years later. Since then it has steadily increased in incidence and host range worldwide, and is a known zoonotic agent. In the United States it is the most significant pathogen affecting growth of tilapia aquaculture. Histopathologic descriptions are incomplete and little is known concerning pathogenesis of the disease or virulence mechanisms of the organism. A composite of lesions was compiled from diseased tilapia evaluated by the Aquatic Animal Disease Diagnostic Laboratory, Louisiana State University from 1995--2001. In common with …

Habitat Ecology Of The Native Subtidal Snail, Lacuna Vincta, In The Gulf Of Maine And The Impact Of Two Introduced Species, Suchana Chavanich

Doctoral Dissertations

Lacuna vincta (Montagu) is a small native herbivorous gastropod that feeds and lives on algae within the rocky subtidal zone of New England. In this study, a combination of field samplings and laboratory experiments were conducted in order to examine the seasonal abundance, feeding preference, and growth of snails on nine different algal species. The results showed that there were differences in the seasonal abundance patterns of L. vincta populations on different algal species. However, the snail populations in all size classes were found year round on Laminaria saccharina (L.) Lamour. Feeding preference experiments showed that L. vincta preferred Antithamnionella …

Detection Of Giardia Lamblia And Cryptosporidium Parvum In The Eastern Oyster (Crassostrea Virginica) Harvested From The Great Bay Estuary, Kim Marie Stowell

Doctoral Dissertations

The Great Bay Estuarine system is being impacted by point source and nonpoint source pollution that affect shellfish quality. Many outbreaks of human gastroenteritis are potentially caused by the consumption of raw or undercooked oysters in which the protozoan pathogens, Giardia lamblia and Cryptosporidium parvum are present. The development of a rapid and sensitive technique to detect infectious protozoa in oysters is a necessity.

Immunofluorescence has been employed as a technique for the detection of these organisms in drinking water. Cross reactivity with algae and the production of false positive results limits the usefulness of this technique in environmental studies. …

The Relationship Between Fruit Color Traits And Anthocyanin Genes In Diploid Fragaria, Chaoyang Deng

Doctoral Dissertations

A candidate gene approach was used to determine the likely molecular identity of the c locus (yellow fruit color) in Fragaria vesca, a diploid (2n = 2x = 14) strawberry. Using PCR with degenerate primer pairs, intron-containing segments of structural genes coding for the enzymes: chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanindin synthase (ANS), and one Del-like regulatory gene (RAN) in the anthocyanin biosynthetic pathway were amplified, cloned and sequenced. Intron length polymorphisms for each of these genes were detected among three diploid varieties: F. vesca Alpine variety 'Yellow Wonder' (YW) (Europe); DNIC, an …

Regulation Of Mammalian Photoreceptor Phosphodiesterase (Pde) By Its Noncatalytic Gaf Domains And Its Two Small Subunits, Gamma And Delta, Hongmei Mou

Doctoral Dissertations

cGMP phosphodiesterase (PDE) is the central effector of visual transduction in retinal rod photoreceptors. The overall goal of this work was to investigate the possible regulatory mechanisms of PDE in mammalian rod photoreceptors by its noncatalytic cGMP binding sites on the PDE catalytic dimer (Palphabeta), and by the interactions between the inhibitory Pgamma subunit and Palphabeta in their phosphorylated and non-phosphorylated states.

First, the binding of cGMP to the noncatalytic sites on membrane-associated PDE (PDE-M) and soluble PDE (PDE-S) was characterized. We found that PDE-M holoenzyme contains 2 non-identical high-affinity cGMP binding sites; one of the cGMP binding sites is …

Nitric Oxide And Cnidarian-Dinoflagellate Symbioses: Pieces Of A Puzzle, Henry G. Trapido-Rosenthal, Katherine H. Sharp

Arts & Sciences Faculty Publications

The presence of nitric oxide synthase (NOS) activity is demonstrated in the tropical marine cnidarian Aiptasia pallida and in its symbiotic dinoflagellate algae, Symbiodinium bermudense. Enzyme activity was assayed by measuring the conversion of arginine to citrulline. Biochemical characterization of NOS from Aiptasia was characterized with respect to cellular localization, substrate and cofactor requirements, inhibitors, and kinetics. In response to acute temperature shock, anemones retracted their tentacles. Animals subjected to such stress had lower NOS activities than did controls. Treatment with NOS inhibitors caused tentacular retraction, while treatment with the NOS substrate L-arginine inhibited this response to stress, as did …

Introduction: Fear And Loathing Of Evolutionary Psychology In The Social Sciences, Daniel Leger, Alan Kamil, Jeffrey French

Psychology Faculty Publications

When one looks at the intellectual landscape of the modern university, at the scholarly and scientific interests of its faculty, the panorama is seamless. There are no discontinuities. The interests of physicists transmogrify into those of chemists, those of chemists into those of biologists, and so on. The lines, the divisions, between departments have been created out of administrative, not intellectual, necessity.

Isolation And Characterization Of A Rhodobacter Capsulatus Hemc Mutant., Karen Coleman Sullivan

LSU Historical Dissertations and Theses

Rhodobacter capsulatus, a purple, nonsulfur photosynthetic bacterium, uses the tetrapyrrole pathway to synthesize four end products: heme, bacteriochlorophyll, vitamin B12, and siroheme. This laboratory has focused on the regulation of the common pathway leading from aminolevulinate to protoporphyrin IX in R. capsulatus. The common portion of the pathway is regulated up to 100-fold by changes in oxygen tension. Research on the regulation of this pathway has been hampered due to a lack of mutants. Until now, the only mutants isolated which block heme production are hemA mutants, which lack aminolevulinate synthase. Since R. capsulatus lacks a cytochrome-independent growth mechanism, mutations …

The Role Of Immunity In Resistance Of Gulf Coast Native Sheep To Haemonchus Contortus Infection., Maria Teresa Pena

LSU Historical Dissertations and Theses

Haemonchus contortus is a serious constraint for sheep production in tropical and subtropical regions of the world. The use of genetically resistant animals is a promising alternative for controlling nematode infections without relying on the use of anthelmintics. Extensive epidemiological studies demonstrated that Gulf Coast Native sheep are naturally resistant to H. contortus infection, but the mechanism underlying this resistance is not well known. The main purpose of this research was to define the components of the immune response that may be involved in resistance of GCN to H. contortus infection. Three studies were conducted. In the first study, a …

Factors Affecting Community Structure Of Mangroves Associated With Point Bars And Islands In A Costa Rican Estuary., Patricia Delgado-Sanchez

LSU Historical Dissertations and Theses

A conceptual model of relationships between mangrove community structure and their physico-chemical environment is developed for point bars and islands in the Tempisque-Bebedero estuarine system, Pacific coast, Costa Rica. The model identifies key variables whose relationships to mangrove forest structure are the focus of extended field and mesocosm studies. Point bars and islands are very dynamic features constantly modified by hydrology and sediment dynamics. In the Tempisque-Bebedero system, they are additionally modified by extensive agricultural activities. High riverine sediment loads, associated with irrigation and seasonal wind-driven resuspension, result in significantly higher sediment deposition in lower intertidal zones; upper intertidal zones …

Systemic And Colonic Hemodynamic And Vasomotor Responses To Adenosine Triphosphate In Horses., Joanne Tetens

LSU Historical Dissertations and Theses

Clinically healthy horses were instrumented to measure hemodynamic, metabolic, hematologic, and serum biochemical variables and monitor clinical signs during and after IV infusion of ATP-MgCl2. Conscious horses were administered ATP-MgCl2 (0.05 mg ATP/kg body weight/min; 0.05 mg/kg/min increments; maximum rate-1.0 mg/kg/min), which caused a rate-dependent increase in cardiac output, decrease in systemic vascular resistance, and mild pulmonary hypertension. The maximal safe infusion rate was 0.3 mg ATP/kg body weight/min. Anesthetized horses administered ATP-MgCl2 (0.1 to 1 mg/kg/min; 0.1 mg/kg/min increments) developed a rate-dependent decrease in systemic and colonic vascular resistance via vasodilatation. In conscious horses administered lowdose endotoxin, ATP-MgCl2 (dose-100 …

Epidemiology Of Salmonella In The Green Iguana (Iguana Iguana)., Mark Anthony Mitchell

LSU Historical Dissertations and Theses

The incidence of iguana-associated salmonellosis reported in humans during the 1990's is a public health concern. This research is the first attempt to describe the epidemiology of Salmonella in the green iguana. Seasonal prevalence of Salmonella in green iguanas and their environment were estimated at a commercial iguana farm in El Salvador. The prevalence of Salmonella was lower in adult iguanas (44%) than in yearlings (50%) (Odds ratio (OR): 0.77, 95% Confidence Intervals (CI): 0.6--0.96) and higher in male iguanas (50%) than females (41%) (OR: 1.5, 95% CI: 1.2--1.8). Salmonella recovery was lower in the fall (41%) sampling period than …

Meiofaunal Colonization Of Artificial Substrates., Nazan Atilla

LSU Historical Dissertations and Theses

Meiofaunal colonization of artificial substrates was investigated in a shallow estuarine embayment. Meiofauna colonized various artificial substrates rapidly, at a rate of 1000 individuals collector-1 day -1 regardless of season, suggesting that high abundances of meiofauna commonly exist in the water column. These water-column meiofauna may be important in fish diets and may serve as a dispersing pool that aids recolonization after disturbance events. Colonization of artificial substrates by transient meiofauna of unknown origin(s) occurred through the water column. To determine the source of meiofauna colonizing artificial substrates, sediment and pier-piling meiofauna were sampled and compared to artificial-substrate colonists. Assemblages …

A Drifter Study Of Advection, Deformations, And Patch Variances With Application To Larval Transport And Dispersal In Barataria Bay, Louisiana., Terry L. Schaefer

LSU Historical Dissertations and Theses

Field studies were conducted to characterize flow fields and their effect on larval transport and retention within Barataria Bay, Louisiana. Drifter tracking and passive larval sampling was conducted monthly during the spring and summer months from 1994 through 1996. Fifteen drifter tracking sessions were conducted over full tidal cycles (diurnal). Drifter positions were determined approximately every thirty minutes using a GPS receiver. A spline interpolation was used to estimate drifter positions at synchronous five-minute intervals. An analytical methodology of Okubo and coworkers was used to compute deformations; and changes in patch variances from the drifter positions. Mean tidal advection and …

T -Cell Cytokines And Equine Nematode Infections., Jenifer Dee Edmonds

LSU Historical Dissertations and Theses

To address the role of parasites on subsequent antigenic challenge, humoral, lymphoproliferative and cytokine responses to a single intramuscular injection of keyhole limpet haemocyanin (KLH) were compared between groups of ponies with high, medium or low gastrointestinal parasite burdens. Heavy and moderately parasitised animals showed a trend towards reduced KLH-specific lymphoproliferation and reduced antigen specific total immunoglobulin, IgG(T) and IgA compared to lightly parasitised ponies. The peripheral blood mononuclear cells (PBMC) from medium and heavily parasitised ponies also had significantly lower levels of IL-4. These data indicate that heavily parasitised animals have uniformly decreased cellular and humoral immune responses to …

Body Condition, Leptin, And Reproductive Characteristics In Horses., Laura Roland Gentry

LSU Historical Dissertations and Theses

A series of experiments was conducted to gain a better understanding of the effects of nutrition and hormonal manipulation on the reproductive processes of the horse. In Experiment 1, body condition score (BCS) and ultrasonic backfat measurements were highly correlated in mares, especially over the tailhead area. In Experiment 2, high BCS (HBCS) mares continued to ovulate during the winter anestrous period, whereas low BCS (LBCS) mares went deeply anestrous. Daily hormone concentrations were not affected by BCS, however, responses to hormonal challenges indicated cyclicity in HBCS mares and reproductive quiescence in LBCS mares. In Experiment 3, treatment of average …

Effects Of Nitric Oxide Synthase Inhibitors On Equine And Bovine Follicular Dynamics And Steroidogenesis., Carlos Roberto Fontes Pinto

LSU Historical Dissertations and Theses

Current scientific literature has shown that: (1) NO is a pro-ovulatory agent and inhibition of its production inhibits ovulation, and (2) NO has strong antisteroidogenic activity, especially on estradiol (E2) production by granulosa cells. The experiments described in this dissertation were designed to answer the following questions involving effects of NO on ovarian physiology: (1) is the inhibitory effect of nitric oxide synthase (NOS) inhibitors on ovulation irreversible (follicular atresia) or temporary (delayed ovulation)? and (2) what is the relationship between NO and hCG-induced preovulatory luteinization? Accordingly, cycling mares were subjected to treatment with NOS inhibitors (L-NAME or aminoguanidine) during …