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Paleoclimate Estimates From The Late Cretaceous San Juan Basin Using Leaf Physiognomy., Frederick Vogt

Student Work

Physiognomy of fossil leaves collected from Late Cretaceous floodplain sediments in present-day northwestern New Mexico was used to estimate paleoclimate. Woody dicot species were collected from this area to determine the Mean Annual Temperature (MAT) and Mean Annual Precipitation (MAP) using both uni- and multi-variate methods. From the same stratigraphic level at the contact between the upper Fruitland and lower Kirtland Formations, 188 specimens from three sites representing twenty-five morphotypes were sampled. Specimens were plotted on a collection curve to ensure species numbers approached saturation during sampling. Leaf margin analysis, a technique that compares the percentage of entire margin to …

Ecological Conditions Of The Papillion Creek Watershed: Effects Of Adjacent Land-Use., Pamela D. Cox

Student Work

Stream conditions were assessed for past and present landscapes of the Papillion Creek Watershed of northwest Omaha, Nebraska based on historical records, present land-use surveys and field data collected in June 2000 using the Environmental Protection Agency’s Rapid Bioassessment Protocol modified to meet the needs of the study. Less than 0.4% of the historic tallgrass Prairie remains, with the present landscape mostly in agriculture (83%) or residential-commercial developments (16%). No significant differences (P ≤ 0.05) were found between ten habitat parameters measured for each of three land-used categories, cultivated, residential-commercial, and other. The overall impact of increased land-use on the …

Mutagenesis Induced By The Tumor Microenvironment: Implications Of Increased Dna Damage And Diminished Dna Repair, Jianling Yuan

Yale Medicine Thesis Digital Library

Tumors are characterized by microenvironmental heterogeneity, with regions of hypoxia, low pH, and nutrient deprivation. It has been proposed that such conditions may be an important factor contributing to cancer genetic instability. Using a chromosomally based lambda phage shuttle vector as a mutation reporter, we show that growth of cells in hypoxia and/or at low pH results in elevated mutation frequencies in two different reporter genes. To elucidate the mechanism of the tumor microenvironment-induced genetic instability, we first measured the production of DNA damage upon hypoxia and re-oxygenation in culture. We found that under such conditions, the intracellular level of …

Community And Ecosystem Analysis Of Forests Recovering From Landslide Disturbance: White Mountain National Forest, New Hampshire, David M. Bryant

Doctoral Dissertations

Sites recovering from landslide disturbance offer many opportunities to study ecosystem processes under extreme conditions. Landslides reset the topographic, microclimatic, parent material and vegetation state factors of ecosystem development. Water, and nutrient resources following landslides are more heterogenously distributed. Soil structure and development is disrupted. Solar insolation and diurnal temperature fluctuation exceed that of the surrounding forest. Consequently, plant colonization and community succession differ from less severely disturbed sites such as timber harvest or agricultural afforestation.

Two chapters of this dissertation address the unique conditions of landslide ecosystem development. Chapter 2 compares historical data collected in 1956 on a chronosequence …

Photoprotective Role Of Beta -Carotene And Antioxidant Enzymes: A Shield Against Ultraviolet Damage In Dunaliella Bardawil, Andrea Lynn Grossman-White

Doctoral Dissertations

Photosynthetic and antioxidant responses following exposure to an array of irradiances and frequencies were examined and contrasted in two species of the unicellular green alga Dunaliella. Species selection was based on the ability of Dunaliella bardawil (UTEX 2538) to accumulate massive quantities of inter-thylakoid beta-carotene during exposure to stress or high irradiances of photosynthetically active radiation (PAR: 400-700 nm) while Dunaliella salina (UTEX 200) lacks this ability. Cells were cultured in two irradiances (150 and 35 mumol photons ·m-2·s -1), and then exposed to high red (wavelengths > 590 nm) or blue light (390-540 nm; 150 mumol photons·m -2·s--1), ultraviolet-A (320-400 …

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 …

Influences Of Social And Habitat Features On Selection And Use Of Breeding Habitat And Pup Survival In South American Fur Seals, Monica Anne Stevens

Doctoral Dissertations

Quantitative information is lacking about how fur seals use habitat and how this use influences fitness. Such information is important for understanding the prospects for recovery of declining populations like those of South American fur seals (Arctocephalus australis) in Peru. In this study I examined the influences of habitat features and human disturbance on selection of breeding habitat by female fur seals in Peru; and I examined how mortality of pups was influenced by habitat features, female behavior, and the social environment on the beach.

Arctocephalus australis in Peru have declined gradually over the past decade, and declined dramatically (72%) …

Birth, Death And Taxis: North Atlantic Right Whales In The Twenty-First Century, Scott Douglas Kraus

Doctoral Dissertations

Twenty two years of North Atlantic right whale data were analyzed. Several measures indicate reproduction in North Atlantic right whales is in a decline. Calving intervals have increased from about 3.3 years in the 1980's to over 5 years, and the age of first parturition is estimated to be 11 years. Females may lose calves before they are detected, artificially increasing the apparent age of first parturition and possibly affecting estimates of calving interval. Northern feeding habitat use patterns do not appear to affect reproduction.

Right whale mortality data was analyzed by age, sex, and habitat use patterns. A total …

Expression, Activation, And Regulation Of Matrix Metalloproteinase 2 (Mmp-2) In The Bovine Corpus Luteum, Bo Zhang

Doctoral Dissertations

Matrix metalloproteinases (MMPs) have been postulated to be important for angiogenesis and for tissue remodeling events associated with corpus luteum (CL) development. The MMPs are mainly regulated at three levels, transcription, activation, and inhibition by endogenous tissue inhibitors of metalloproteinases (TIMPs). Unlike most MMPs, pro-MMP-2 activation is accomplished on the cell surface rather than extracellularly. The objectives of the present study were to clone bovine cDNAs for MMP-2 and its activator, membrane type 1- (MT 1-)MMP, to investigate the expression and localization of MMP-2, MT1-MMP, TIMP-1, and TIMP-2 in three ages of CL, and to explore the regulation of MMP-2 …

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 …

Genetic Basis Of Adaptive Radiation In East African Cichlids, Richard Craig Albertson

Doctoral Dissertations

East African cichlids are a paramount example of adaptive morphological radiation. The most dramatic difference among species occurs in oral jaw design and correlates with ecological niche partitioning. Convergent evolution of trophic forms between lakes suggests a common mechanism. What combination of intrinsic and extrinsic factors constitute this mechanism still remains to be seen. The goal of this dissertation was to examine the genetic basis of shape differences between two closely related cichlid species that employ alternate modes of feeding. This was achieved through a number of independent experiments. First, I used field data to characterize the way in which …

The Effects Of Erythrocyte Alloantigen L On The Avian Immune Response, Zdravka Ognyanova Medarova

Doctoral Dissertations

Experiment 1 examined the alloantigen system L effects on Rous sarcomas in three B complex genotypes. The parental stock were 50% Modified Wisconsin Line 3 and 50% inbred Line 6.15- 5. B2B5 L1L2 x B2B5 L 1L2 matings produced experimental chicks. Chicks were inoculated with 20 pock-forming units (pfu) Rous sarcoma virus (RSV) at 6 weeks-of-age. Tumors were scored six times over 10 weeks postinoculation. Tumor scores were used to assign a tumor profile index (TPI) to each chicken. Results were evaluated by ANOVA. The B complex affected the responses. Separate analyses revealed L system effects ( P < 0.05) only in B5B 5 chickens.

Experiment 2 …

Evolution Of Gender Associated Mitochondrial Dna In Bivalves, Jason Paul Curole

Doctoral Dissertations

Bivalves of the families Unionidae and Mytilidae possess a unique mode of mitochondrial DNA inheritance dubbed sex-limited mitochondrial DNA (mtDNA) inheritance or doubly-uniparental inheritance (DUI). In contrast to the matrilineally restricted inheritance of mtDNA in other metazoans, these bivalves have both matrilineally and patrilineally inherited mtDNA lineages. Although the matrilineally inherited mtDNA (or F type) is present in the somatic tissues of both sexes and the female gonad, the patrilineally inherited mtDNA (or M type) is limited to the male gonad. In Mytilus several observations have been made concerning the evolution of DUI. Firstly, the fidelity of DUI is not …

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 …

Impacts Of The Introduced Crabs, Carcinus Maenas And Hemigrapsus Sanguineus, In Northern New England, Megan Conlon Tyrrell

Doctoral Dissertations

Two introduced crab species are presently found in northern New England, Carcinus maenas, which has been in this region for over 100 years, and Hemigrapsus sanguineus which was first reported in New Hampshire in 1998. Carcinus maenas is a generalized predator and its introduction has had negative effects on several native mollusc species but the community wide impacts of its introduction have been relatively neglected. Hemigrapsus sanguineus is just beginning to establish populations in this region, and its effects on the resident community are unknown. Both monitoring and experimental approaches were used to retroactively infer the impacts of C. maenas …

Assessing Ice Storm Damage To Hardwood Forest Canopies Using The Advanced Solid-State Array Spectroradiometer (Asas) And Landsat Tm Imagery, James Stuart Burnett

Doctoral Dissertations

A major ice storm in January 1998 damaged 17 million acres of forestland in the Northeastern United States and Quebec Province. In July 1998 the airborne multiangle hyperspectral sensor, Advanced Solid-State Array Spectroradiometer (ASAS), acquired imagery for nine ice damaged target areas in the White Mountain National Forest (WMNF). Ice damage was also measured in situ at 288 sample plots. Radiance values for nadir ASAS images were normalized and the blue shift of the red edge was represented as the radiance value at 714 nm (714nr). The 714nr for 210 sites in 3 damage classes differentiated severely damaged sites from …

Ompd But Not Ompc Is Involved In Adherence Of Salmonella Enterica Serovar Typhimurium To Human Cells, Bochiwe Hlezipi Hara-Kaonga

Doctoral Dissertations

Salmonella enterica serovar Typhimurium expresses three major outer membrane proteins: OmpC, OmpF, and OmpD. Conflicting reports exist regarding the role of OmpC and OmpD in the pathogenesis of this organism. This study investigated the role of OmpC and OmpD in adherence to human U937 macrophages and T84 intestinal epithelial cells. OmpC and ompD mutant strains were created by transposon mutagenesis utilizing P22-mediated transduction of Tn10 and Tn 5 insertions into wild-type strain 14028. Fluorescein-labeled wild-type and mutant bacteria were incubated with PKH26-labeled T84 cells at various bacteria-to-cell ratios for 1 h at 37 C. Single and dual fluorescence of samples …

Comparative Anatomy And Evolution Of The Gastrotrich Muscular System, Richard Hochberg

Doctoral Dissertations

Gastrotrichs figure prominently in metazoan phylogeny because they share a suite of complex morphological characteristics with several other members of the Bilateria. But their microscopic size, cryptic interstitial habitat, and lack of fossil record have exacerbated the usual barriers to phylogenetic analysis. To arrive at a better understanding of gastrotrich systematics and evolution, cladistic analyses and detailed studies of the muscular system were performed.

A fluorescent F-actin stain was applied to whole mounts of 26 species of Gastrotricha to characterize the musculature. Muscle patterns were mapped, their functions inferred, and the direction of evolution hypothesized for several families. The musculature …

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 …

Morphological And Physiological Studies Of The Primary Olfactory Pathway In The Sea Lamprey, Petromyzon Marinus: Spatial Organization Of Discrete Glomerular Subsets And The Development Of Functional Imaging For Monitoring Glomerular Activity., Andrea. Frontini

Electronic Theses and Dissertations

Olfaction is an extremely important communication modality for most organisms, yet it is probably the sensory system least understood. Recent findings have shed light on some of the basic principles that control olfactory detection and transmission of signals into the central nervous system, but the mechanisms for spatial resolution of odorants within the brain are still poorly understood. In this study we have used histological, immunocytochemical and in vivo optical imaging techniques to investigate the spatial and functional organization of olfactory bulb glomeruli of the developing Agnathan, the sea lamprey, Petromizon marinus. We characterized the glomerular pattern of olfactory sensory …

Morphology And Histochemistry Of The Peripheral Olfactory Organ And Behavioural Responses By The Round Goby, Neogobius Melanostomus , To Putative Pheromones And Conspecific Extracts., Rachelle Marie. Belanger

Electronic Theses and Dissertations

This study links the anatomy of the peripheral olfactory organ in the bottom-dwelling round goby (Neogobius melanostomus) with behavioural responses to putative pheromones and conspecific extracts. The spatial organization of the nasal cavity was examined using impression material injection, immunocytochemistry, and transmission electron microscopy. The peripheral olfactory organ had a compact structure with an olfactory chamber that contained a single longitudinal lamella. Prominent dorsocaudal lachrymal and ethmoid accessory nasal sacs were situated ventrocaudal to the chamber. The location of the olfactory mucosa within the olfactory chamber is novel for teleost fish, as it extends dorsally beyond the ventral surface. Microvillar …

Cultivation Of Medicinal Plants In Greenhouse Hydroponics., Dana. Simeunovic

Electronic Theses and Dissertations

Interest in medicinal plants as an alternative crop for greenhouse growers was the impetus for this project, as little information exists on the commercial production of medicinal plants in hydroponics under greenhouse conditions. This research project was designed to (1) identify medicinal plants with commercial potential, (2) evaluate their suitability for greenhouse hydroponic growth, (3) determine optimal concentrations and ratios of nutrient solutions, and (4) manipulate nitrogen levels as a possible regulator of leaf tissue production and of secondary metabolite production in two medicinally important plants, Hypericum perforatum and Tanacetum parthenium . Once nutrient regimes had been optimized to give …

Methods For Antigen And Nucleic Acid Analysis., Bakhos Antonios. Tannous

Electronic Theses and Dissertations

One aspect of this dissertation involves the investigation of T7 RNA polymerase (T7RP) as a label for antigen quantification. In an in vitro, coupled (one-step) transcription/translation reaction, T7RP catalyzes the expression of an enzyme-coding DNA template to produce free enzyme (luciferase) in solution. We demonstrate that the generated luciferase is linearly related to the input T7RP in a range covering over four orders of magnitude. It is also shown that T7RP exhibits a significant level of self-replication (100-fold) in vitro by acting on a DNA template comprising the T7RP cDNA downstream of a T7 promoter. By combining the self-replication reaction …

Patterns Of Habitat, Microhabitat, And Body Size Distribution In A Lizard Assemblage., Sarah Elizabeth. James

Electronic Theses and Dissertations

I investigated habitat use within an assemblage of four phrynosomatine lizards (Sceloporus graciosus, S. undulatus, Urosaurus ornatus, and Uta stansburiana) that are commonly syntopic in the pinyon-juniper woodland habitat on the elevated mesas of western Colorado. Lizard populations were censused within Colorado National Monument, U.S.A., during the summer months of 1989, 1990, 1991, 1992, 2000 and 2001. Microhabitat characteristics surrounding capture points were recorded in 1990, 1992 and 2000, and captures were classified into one of two distinct habitats in 2001. All four species used dead trees more frequently than live trees, despite an opposite pattern of availability. Overall density …

Bimodal Return Distribution In A Northern Population Of Salmon: Genetic, Life History, And Habitat Analysis Of Adult And Juvenile Sockeye Salmon (Oncorhynchus Nerka)., Elizabeth Kathleen. Fillatre

Electronic Theses and Dissertations

Bimodal return migration patterns are evident in many populations of North American salmonids. This thesis analyzes how bimodal return distribution affects genetic structure, life history, and habitat partitioning in a Northern population of sockeye salmon (Oncorhynchus nerka). This thesis is divided into two sections; (1) adult population genetics and (2) juvenile habitat distribution. Genetic analysis of adult spawners using eight microsatellite loci indicates that the early and late runs are genetically divergent in all seven years analyzed (1994--2000), and that differentiation is greater between the runs than among the seven years analyzed. Life history analysis (age at maturation, sex ratio, …

Use Of Calcified Structures For Stock Discrimination In Great Lakes Walleye (Stizostedion Vitreum)., Kevin James. Hedges

Electronic Theses and Dissertations

Stock discrimination has been, and will continue to be, of interest to population ecologists and fisheries managers. Morphological, genetic and microchemical techniques have been applied in stock discrimination projects with varying degrees of success. The selection of an appropriate technique in each instance is important and comparative studies are necessary to understand system specificity and the effects of technological developments. This thesis concerns the development and assessment of otolith microchemistry, and the assessment of otolith morphology, for application to stock discrimination within the Lake Erie walleye ( Stizostedion vitreum) fishery. Larval walleye were collected from various spawning sites in spring …

Secondary Production, Trophic Position, And Potential For Accumulation Of Polycyclic Aromatic Hydrocarbons In Predatory Diptera In Four Wetlands Of The Athabasca Oil Sands, Alberta, Canada., Kevin Dean Ganshorn

Electronic Theses and Dissertations

Larvae of aquatic Diptera are important predators in fishless wetlands of northeast Alberta. Annual production was estimated for benthic (Chironomidae: Tanypodinae) and pelagic (Chaoboridae: Chaoborus) dipteran populations in 4 wetlands in surface-mined areas of the Athabasca oil sands, two of which received oil sands mine process material (OSPM; containing polycyclic aromatic hydrocarbons (PAHs)), and two of which were reference wetlands. The structure of benthic and pelagic food webs was estimated by measuring stable carbon and nitrogen isotopes. Stable nitrogen isotopes were also used to determine trophic levels of Tanypodinae and Chaoborus in order to determine their potential to bioaccumulate PAHs. …

Interspecific Interactions Between Mayflies (Hexagenia ) And Midges (Chironomus)., Wes. Plant

Electronic Theses and Dissertations

Both Hexagenia (mayfly) nymphs and Chironomus (midge) larvae live in the soft sediments of Lake Erie, showing a non-overlapping mosaic distribution. The objective of this study was to quantify the importance of interactions between Hexagenia nymphs, and larval Chironomus. The field distributions of Hexagenia nymphs and chironomid larvae were analysed to examine the co-occurance of these two taxa. Little evidence of negative interactions between these taxa were found based on these analyses. Laboratory experiments were conducted that measured survivorship and increase in body length of Hexagenia nymphs and Chironomus larvae reared individually and together to determine the strength of competition …

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 …

Virtual, On-Line, Frog Dissection Vs. Conventional Laboratory Dissection: A Comparison Of Student Achievement And Teacher Perceptions Among Honors, General Ability, And Foundations Level High School Biology Classes, Ronald H. Kopec

Seton Hall University Dissertations and Theses (ETDs)

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