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A Vascular Flora Of Jackson County, Alabama, Kristin Renée Brodeur

Theses

The county is herein documented to support 1,272 species and infraspecific taxa. During the course of this study, 359 county records were produced, and 18 new taxa were recorded as occurring in the state for the first time. The vascular flora is demonstrably rich, even in comparison to other ecosystematic studies completed within the State. In contrast to other counties and in conformity with a long land and water use history, Jackson County has nearly 20% of the flora comprising alien taxa. As expected and evidenced by the life-form spectra dominated by hemicryptophytes and therophytes, the species are well-adapted to …

Review Of Population Biology Of Grasses, Thomas B. Bragg

Biology Faculty Publications

Population Biology of Grasses provides a wealth of knowledge beyond population biology that ecologists and ecosystem biologists will find relevant to their concerns, particularly those with an interest in grasslands. Though not limited to the Great Plains region, the book would make an excellent addition to the reference shelf of anyone interested in grasses and grassland-related ecosystems, including readers with an interest in land management and preservation. While the papers are written for different levels of readers, all provide information accessible to non-specialists.

Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá

Virginia Journal of Science

Reconstructing three dimensional structures (3DR) from histological sections has always been difficult but is becoming more accessible with the assistance of digital imaging. We sought to assemble a low cost system using readily available hardware and software to generate 3DR for a study of tadpole chondrocrania. We found that a combination of RGB can1era, stereomicro­scope, and Apple Macintosh PowerPC computers running NIH Image, Object Image, Rotater, and SURFdriver software provided acceptable reconstruc­tions. These are limited in quality primarily by the distortions arising from histological protocols rather than hardware or software.

Cartilage Regeneration On A Large Articular Surface Facilitated By Stress Shielding, Charles L. Mcdowell, Jennifer S. Wayne, Robert Tuten, Hunter H. Mcguire Jr.

Virginia Journal of Science

An animal model for the study of articular cartilage regeneration in-vivo facilitated by stress-shielding is introduced. The object of the model is to test the hypothesis that some form of cartilaginous tissue will grow upon a large joint surface in vivo with the joint in normal motion. The model utilizes the known capability of immature cells to differentiate. The source of cells is bleeding subchondral bone. In addition, the model provides a mechanically shielded environment in which cell differentiation and maturation can occur. The study showed that a substantial amount of tissue will grow in the animal model only when …

Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls

Faculty Publications

No abstract provided.

Measurement Of Oxygen Partial Pressure, Its Control During Hypoxia And Hyperoxia, And Its Effect Upon Light Emission In A Bioluminescent Elaterid Larva, G. S. Timmins, C. A. A. Penatti, E. J. H. Bechara, H. M. Swartz

Dartmouth Scholarship

This study investigates the respiratory physiology of bioluminescent larvae of Pyrearinus termitilluminans in relation to their tolerance to hypoxia and hyperoxia and to the supply of oxygen for bioluminescence. The partial pressure of oxygen (P(O2)) was measured within the bioluminescent prothorax by in vivo electron paramagnetic resonance (EPR) oximetry following acclimation of larvae to hypoxic, normoxic and hyperoxic (normobaric) atmospheres and during periods of bioluminescence (during normoxia). The P(O2) in the prothorax during exposure to an external P(O2) of 15.2, 160 and 760 mmHg was 10.3+/-2.6, 134+/-0.9 and 725+/-73 mmHg respectively (mean +/- s.d., N=5; 1 mmHg=0.1333 kPa). Oxygen supply …

Makaira Sp., Cf. M. Nigricans Lacépède, 1802 (Teleostei: Perciformes: Istiophoridae) From The Late Miocene, Panama, And Its Probable Use Of The Panama Seaway, Harry L. Fierstine

Biological Sciences

A nearly complete rostrum (USNM 358534) similar in morphology to the extant bluc marlin, Makaira nigricans Lacepede 1802, is identified from the GaUln Formation (late Miocene, Panama). Identification is based on comparison with a large series of Recent istiophorid species and with fossil species of the genus Makaira. The Gatlin specimen and additional examples from other fossil vertebrates provide evidence that the ancient Panama Seaway probably was a travel route between the Atlantic and Indo-Pacific for large marine vertebrates during the middle Miocene to earliest Pliocene. This is the first record of an istiophorid billfish from the Gatlin Fonnation and …

Variation And Repeatability Of Calling Behavior In Crickets Subject To A Phonotactic Parasitoid Fly, Gita R. Kolluru

Biological Sciences

Male Teleogryllus oceanicus (Orthoptera: Gryllidae) produce a conspicuous calling song to attract females. In some populations, the song also attracts the phonotactic parasitoid fly Ormia ochracea (Diptera: Tachinidae). I examined the factors affecting calling song by characterizing the calling behavior of caged crickets from an area where the fly occurs. Calling activity (proportion of time spent calling) was repeatable and a significant predictor of female attraction. However, calling activity in the parasitized population was lower than in an unparasitized Moorea population (Orsak, 1988), suggesting a compromise between high activity to attract females and low activity to avoid flies. Calling activity …

Segmental Distribution Of Common Synaptic Inputs To Spinal Motoneurons During Fictive Swimming In The Lamprey, James T. Buchanan, Stefan Kasicki

Biological Sciences Faculty Research and Publications

These experiments were designed to measure the degree of shared synaptic inputs coming to pairs of myotomal motoneurons during swimming activity in the isolated spinal cord of the lamprey. In addition, the experiments measured the decrease in the degree of shared synaptic inputs with the distance between the motoneurons to assess the segmental distribution of these shared inputs. Intracellular microelectrode recordings of membrane potential were made simultaneously on pairs of myotomal motoneurons during swimming activity induced with an excitatory amino acid. The swim cycle oscillations of motoneuron membrane potentials were removed with a digital notch filter, thus leaving the fast …

Gender Variation In Croton Californicus (Euphorbiaceae), James Lynwood Smith Ii

Loma Linda University Electronic Theses, Dissertations & Projects

Croton californicus Muell. Arg. (Euphorbiaceae) is a subshrub suspected of being dimorphic with phase choices. Gender variation in C. californicus was studied in natural populations of southern California for three years (1994-96) to observe patterns of gender !ability. Some sites exhibited significantly male-biased sex ratios, and these sites often had the greatest number of monoecious morphs, cosexual plants with unisexual flowers. Gender variation was quantified for cosexual plants by calculating the Estimated Floral Gender (EFG) which varied from 1.00 (female) to 0.00 (male). The distribution of the EFG was highly skewed towards maleness. Monoecious individuals were then categorized by …

Molecular Systematics & Evolution Of The Ctenosaura Hemilopha Complex (Squamata: Iguanidae), Michael Ray Cryder

Loma Linda University Electronic Theses, Dissertations & Projects

Molecular variation within Ctenosaura hemilopha and among other Ctenosaura species are used to identify species boundaries, assess suitable systematic characters, identify evolutionary patterns within C. hemilopha mitochondrial DNA sequences and reconstruct species and area relationships among the various taxa. The molecular evolution of the C. hemilopha complex is analyzed using 1109 base pairs of mitochondrial DNA sequence from the cytochrome b and cytochrome oxidase III genes. Samples come from 22 individuals representing each of the five allopatric populations.

The results of a parsimony analysis showed a strongly supported, partially resolved set of relationships. The strict consenses tee formed in this …

Comparing The Tadpoles Of Hyla Geographica And Hyla Semilineata, Anne D'Heursel, Rafael O. De Sá

Biology Faculty Publications

External morphology, internal oral anatomy, and chondrocranial anatomy were examined for tadpoles of Hyla geographica from the Amazon rainforest, Brazil, and Hyla semilineata from the Atlantic rainforest, Brazil. Here, we provide morphological larval data to help diagnose these closely related species. Scanning electron microscopy analysis of buccal morphology showed the most distinctive features between these species: the distance between the lingual papillae in the buccal floor of H. geographica is three times greater than that distance in H. semilineata, and the relative size of the lingual papillae in H. geographica is less than half their size in H. semilineata. Although …

Host-Driven Population Dynamics In An Herbivorous Insect, Tiina Ylioja, Heikki Roininen, Matthew P. Ayres, Matti Rousi, Peter W. Price

Dartmouth Scholarship

Understanding the nature and relative importance of endogenous (density-dependent) and exogenous (density-independent) effects on population dynamics remains a central problem in ecology. Evaluation of these forces has been constrained by the lack of long time series of population densities and largely limited to populations chosen for their unique dynamics (e.g., outbreak insects). Especially in herbivore populations, the relative contributions of bottom-up and top-down effects (resources and natural enemies, respectively) have been difficult to compare because population data have rarely been combined with resource measurements. The feeding scars of a wood-mining herbivorous insect (Phytobia betulae Kangas; Diptera: Agromyzidae) of birch …

Vegetative Change On South Padre Island, Texas, Over Twenty Years And Evaluation Of Multispectral Videography In Determining Vegetative Cover And Species Identity, Robert I. Lonard, Frank W. Judd, James H. Everitt, David E. Escobar, Mario A. Alaniz, Isabel Cavazos Iii, M. R. Davis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

A comparative vegetation analysis of an island-wide transect of South Padre Island, Texas, was conducted in 1997 using aerial multispectral digital videography and line intercept ground truth techniques to assess the usefulness of videography in estimating vegetative cover and species identifications. Ground truth data were used to assess vegetative change occurring in the 20 years since the report of Judd et al. (1977) on the vegetation of South Padre Island. Estimates of total cover by ground truth and remote sensing techniques were similar (2.45% difference) on South Padre Island. Thus, airborne multispectral digital videography is an effective technique for assessing …

Systematic Changes In Gene Expression Patterns Following Adaptive Evolution In Yeast, Tracy L. Ferea, David Botstein, Patrick O. Brown, R. Frank Rosenzweig

Biological Sciences Faculty Publications

Culturing a population of Saccharomyces cerevisiae for many generations under conditions to which it is not optimally adapted selects for fitter genetic variants. This simple experimental design provides a tractable model of adaptive evolution under natural selection. Beginning with a clonal, founding population, independently evolved strains were obtained from three independent cultures after continuous aerobic growth in glucose-limited chemostats for more than 250 generations. DNA microarrays were used to compare genome-wide patterns of gene expression in the evolved strains and the parental strain. Several hundred genes were found to have significantly altered expression in the evolved strains. Many of these …

Conservation Implications Of Dietary Dilution From Debris Ingestion: Sublethal Effects In Post-Hatchling Loggerhead Sea Turtles, Shannon J. Mccauley, Karen A. Bjomdal

Biological Sciences

Ingestion of anthropogenic debris by marine species has been documented extensively; fewer studies have attempted to quantify the sublethal effects caused by debris ingestion. One potential sublethal effect is reduced nutrient gains from diets diluted by consumption of debris. Post-hatchling and juvenile loggerhead sea turtles (Caretta caretta) consume substantial quantities of debris. We evaluated the effects of dietary dilution on voluntary intake in post-hatchling loggerheads to assess their ability to compensate for the presence of inert diluents in their diet by increasing dry mass intakes to maintain nutrient gains. Mean daily intakes of dry mass did not increase …

Development Of A System For Genetic Manipulation Of Bartonella Bacilliformis, James M. Battisti, Michael F. Minnick

Biological Sciences Faculty Publications

Lack of a system for site specific genetic manipulation has severely hindered studies on the molecular biology of all Bartonella species. We report the first site-specific mutagenesis and complementation for a Bartonella species. A highly transformable strain of B. bacilliformis, termed JB584, was isolated and found to exhibit a significant increase in transformation efficiency with the broad-host-range plasmid pBBR1MCS-2, relative to wild-type strains. Restriction analyses of genomic preparations with the methylation-sensitive restriction enzymes ClaI and StuI suggest that strain JB584 possesses a dcm methylase mutation that contributes to its enhanced transformability. A suicide plasmid, pUB1, which contains a polylinker, a …

Using Atlas Data To Model The Distribution Of Woodpecker Species In The Jura, France, Claudine Tobalske, Bret W. Tobalske

Biological Sciences Faculty Publications

Breeding bird atlases providing distribution data at a regional scale are becoming increasingly common. To assess the ability of such data to develop bread-scale bird-habitat models, we used data from a breeding bird atlas and landscape variables obtained From a geographic information system (GIS) to study the distribution of seven woodpecker species in the Jura, France: the Black (Dryocopus martins), Green (Picus viridis). Grey-headed (P. canus), Great Spotted (Dendrocopos major), Middle Spotted (D. medius), and Lesser Spotted (D. minor) Woodpeckers, and the Wryneck (Jynx torquilla). We used logistic regression to develop predictive models from variables that described each 575-ha atlas …

Avian Communities Of Large Reclaimed Mine Grasslands In Southwestern Indiana, Travis L. Devault

All-Inclusive List of Electronic Theses and Dissertations

Many bird species native to the tallgrnss prairie region oCthc central U.S. have declined drastically since European settlement due lo the destruction and alteration of grassland habitat. In this study, the breeding bird communities or 21 large reclaimed surface coal mine grasslands in a seven-county area or southwestern Indiana were examined with respect to species and guild composition, density, variation among sites, and grassland size. In addition, the vegetation characteristics of nine large mine grasslands were described and related to the presence and abundance or eight grasslund bird species common to the study areas. The immense size of mine grasslands …

Succinate Dehydrogenase (Sdh) From Bradyrhizobium Japonicum Is Closely Related To Mitochondrial Sdh, David J. Westenberg, Mary Lou Guerinot

Dartmouth Scholarship

The sdhCDAB operon, encoding succinate dehydrogenase, was cloned from the soybean symbiont Bradyrhizobium japonicum. Sdh from B. japonicum is phylogenetically related to Sdh from mitochondria. This is the first example of a mitochondrion-like Sdh functionally expressed in Escherichia coli.

Reactive Oxygen Species Generated By Depletion Of Cellular Glutathione Mediate Cadmium Cytotoxicity, Jun Xu

Masters Theses

Studies were put forth to test whether or not reactive oxygen species, which are influenced by the cellular level of reduced glutathione, mediate the toxicity of cadmium. Cadmium has been a focal point in the health care community in the past few years because it has been shown to induce the development of tumors, interfere with cellular signaling, and cause damage to organs, tissues, and biomolecules. Although various studies and theories have been proposed, little direct evidence, especially from studies utilizing primary cells in culture, has accumulated to show the mechanism by which the cadmium induced toxicity occurs.

Our studies …

Two-Metal-Ion Catalysis In Adenylyl Cyclase, John J.G. Tesmer, Roger K. Sunahara, Roger A. Johnson, Gilles Gosselin, Alfred G. Gilman, Stephen R. Sprang

Biological Sciences Faculty Publications

Adenylyl cyclase (AC) converts adenosine triphosphate (ATP) to cyclic adenosine monophosphate, a ubiquitous second messenger that regulates many cellular functions. Recent structural studies have revealed much about the structure and function of mammalian AC but have not fully defined its active site or catalytic mechanism. Four crystal structures were determined of the catalytic domains of AC in complex with two different ATP analogs and various divalent metal ions. These structures provide a model for the enzyme- substrate complex and conclusively demonstrate that two metal ions bind in the active site. The similarity of the active site of AC to those …

The Rise And Fall Of African American Midwifery In The South, Nicole M. Bernard

Electronic Dissertations and Theses

The purpose of this thesis is to give insight into the role played by the African American midwife in the rural south, including Louisiana, Alabama, Texas, and Florida. The African American midwife was responsible for prenatal care, delivery, and a certain degree of postnatal care for the mother and the infant. During slavery, she was all that the slaves had. The African American midwife also aided in delivery of some of the whites as well in a time when blacks were considered to be no more than animals. This proves that the African American midwife was more than a savage …

Effects Of Lead Nitrate Contaminated Soil On Tagetes Erecta (Marigolds), Deetra Dianne Washington

Electronic Dissertations and Theses

This study was developed to determine the effects of lead nitrate on marigold (Tagetes erecta) plants and to determine if these plants could phytoremediate or uptake lead nitrate from the soil. Phytoremediation is a low cost-effective means of reduction or removal of environmental contaminants by plants from the environment and is currently being investigated for many remediation applications. The objectives of this research were to: 1) determine the toxicity of lead nitrate on T. erecta by exposure of the plants to varying concentrations of lead nitrate (0.1-1000 ppm); 2) determine the effects of lead nitrate on the growth and development …

A Genetic Analysis Of The Relationship Between Life-History Variation And Heat-Shock Tolerance In Drosophila Buzzatii, Robert A. Krebs, Volker Loeschcke

Biological, Geological, and Environmental Faculty Publications

Although exposure to environmental stress is common in most populations, and the physiological effects of stress on individuals are well studied, the evolutionary importance of stress to populations is not well understood. To address multitrait responses to environmental change and potential constraints on character evolution, we analysed, in 100 isofemale lines of Drosophila buzzatii, the genetic relationships between resistance to a short heat shock and several life-history traits: survival in benign conditions, larval developmental time, fecundity and longevity. Estimates of heritability of larval thermotolerance were low, but significant, and all life-history traits varied significantly among isofemale lines. Several of …

Different Proctolin Neurons Elicit Distinct Motor Patterns From A Multifunctional Neuronal Network, Dawn M. Blitz, Andrew E. Christie, Melissa J. Coleman, Brian J. Norris, Eve Marder, Michael P. Nusbaum

WM Keck Science Faculty Papers

Distinct motor patterns are selected from a multifunctional neuronal network by activation of different modulatory projection neurons. Subsets of these projection neurons can contain the same neuromodulator(s), yet little is known about the relative influence of such neurons on network activity. We have addressed this issue in the stomatogastric nervous system of the crab Cancer borealis. Within this system, there is a neuronal network in the stomatogastric ganglion (STG) that produces many versions of the pyloric and gastric mill rhythms. These different rhythms result from activation of different projection neurons that innervate the STG from neighboring ganglia and modulate STG …

Diversity Of Microorganisms Isolated From Amber, C. L. Greenblatt, A. Davis, B. G. Clement, Christopher Kitts, T. Cox, Raul J. Cano

Biological Sciences

Claims that organisms can be cultured from amber, if substantiated, would be significant contributions to our understanding of the evolution, tenacity, and potential spread of life. Three reports on the isolation of organisms from amber have been published. Cano and Borucki recently reported the isolation of Bacillus sphaericus and Lambert et al. have described a new species designated Staphylococcus succinus from 25–40 million year old Dominican amber. These characterized organisms were phylogenetically distant from extant relatives and the Staphylococcus sp. sufficiently far removed from other extant staphylococci to be considered a new species. Here we report the culture of bacteria …

The Translocation Of Barramundi. A Discussion Paper., Makaira Pty Ltd

Fisheries Management Papers

There is recognisable economic benefit to the translocation of barramundi, but there is also a need to ensure the translocation will not adversely impact upon the genetic diversity, introduce disease or impact on the natural environment and biodiversity. This discussion paper has been prepared to provide information to assist in the assessment of the possible impact of translocation of barramundi into and within Western Australia, for the purposed of recreational stock enhancement, aquaculture development and domestic stocking. In contemplating the translocation any aquatic species, signigicant economic and social benefits must be balanced with biological and environmental risks; that is, the …

Positions In The 30s Ribosomal Subunit Proximal To The 790 Loop As Determined By Phenanthroline Cleavage, Gregory W. Muth, Scott P. Hennelly, Walter E. Hill

Biological Sciences Faculty Publications

Positioning rRNA within the ribosome remains a challenging problem. Such positioning is critical to understanding ribosome function, as various rRNA regions interact to form suitable binding sites for ligands, such as tRNA and mRNA. We have used phenanthroline, a chemical nuclease, as a proximity probe, to help elucidate the regions of rRNA that are near neighbors of the stem-loop structure centering at nt 790 in the 16S rRNA of the Escherichia coli 30S ribosomal subunit. Using phenanthroline covalently attached to a DNA oligomer complementary to nt 787-795, we found that nt 582-584, 693-694, 787-790, and 795-797 were cleaved robustly and …

Effects Of Fire On The Demography Of The Endangered, Geophytic Herb Silene Spaldingii (Caryophyllaceae), Peter Lesica

Biological Sciences Faculty Publications

Understanding the effects of disturbances such as fire on plant demography helps elucidate the mechanisms that cause changes in community composition. I studied the effects of spring and fall fires on Silene spaldingii, an endangered perennial herb of grasslands in northwest Montana. Individual S. spaldingii plants were mapped, and size and flowering were recorded for 1 yr prior and 5 yr subsequent to the burn treatments. Enhanced seedling recruitment (70–410%) and a 22% increase in population size were the principal effects of fire on S. spaldingii, and fall burn plots had lower recruitment than spring burn plots. These effects were …