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Theses and Dissertations

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Full-Text Articles in Biology

Effects Of Predation Environment And Food Availability On Somatic Growth In The Livebearing Fish Brachyrhaphis Rhabdophora (Pisces: Poeciliidae), Brittany Herrod Gale Mar 2012

Effects Of Predation Environment And Food Availability On Somatic Growth In The Livebearing Fish Brachyrhaphis Rhabdophora (Pisces: Poeciliidae), Brittany Herrod Gale

Theses and Dissertations

Variation in somatic growth rates has interested biologists for decades because of the relationship between growth and other fitness-determining traits (i.e. fecundity, survival, and body size), and the corresponding effect of somatic growth on production of organisms humans use for food. The interaction between genetic variation in growth rates and environmentally induced variation in growth rates shows the pattern of growth across multiple environments (i.e. the reaction norm) that clarifies the history and potential future of evolutionary change in growth rates among populations. Theoretical predictions suggest variation in predator-induced mortality rates can influence mean growth rates and the shape of …

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Phylogenetics Of Thysanoptera (Insecta: Paraneoptera), Rebecca S. Buckman Mar 2012

Phylogenetics Of Thysanoptera (Insecta: Paraneoptera), Rebecca S. Buckman

Theses and Dissertations

The order Thysanoptera (Insecta: Paraneoptera), commonly known as thrips, includes organisms that exhibit a wide range of social and feeding behaviors that are of particular interest in evolutionary studies. These studies within thrips have been inhibited by the lack of knowledge of thrips relationships. The recognized classification scheme strives to reflect evolutionary relationships and is based upon morphology. Molecular data is next as morphology alone is not enough to resolve relationships. Few molecular studies have been conducted and all were limited in their taxon sampling and genetic sampling. To provide a foundation of future evolutionary studies, the objectives of this …

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Response Of Moth Assemblages To Pine-Grassland Restoration For Red-Cockaded Woodpeckers, Kristen Robyn Benjamin Jan 2012

Response Of Moth Assemblages To Pine-Grassland Restoration For Red-Cockaded Woodpeckers, Kristen Robyn Benjamin

Theses and Dissertations

I examined community composition, species richness, and abundance of forest moths in three restored pine-grasslands and three nearby areas with similar site characteristics but no history of restoration management. My study addressed questions of how restoration practices impact moth species richness and abundance, whether distinct moth communities are associated with restored and unrestored plots, how vegetation has responded to restoration treatments, and how moths have responded to vegetation. I expected that changes in moth community composition could be predicted by host specialization, with species having narrow feeding niches occurring in greatest numbers where essential resources were most abundant. As expected, …

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Adam10: A Novel Regulator Of Mast Cell Function And Activation, Travis Faber Jan 2012

Adam10: A Novel Regulator Of Mast Cell Function And Activation, Travis Faber

Theses and Dissertations

In this study we show, to our knowledge, the first description of the role ADAM10 plays on mast cells. ADAM10 is abundantly expressed on mast cells both in vitro and in vivo. Its expression is inhibited by IL-10, a suppressive cytokine. siRNA depletion of ADAM10 on bone marrow-derived mast cells (BMMC) caused decreased IL-6 production following IgE cross-linking and also impaired BMMC stem cell factor (SCF)-induced migration through collagen IV. Mast cells and T helper cells (Th cells) in the peritoneum were reduced in ADAM10 KO mice. In addition, ADAM10 KO BMMC produced significantly less of all cytokines measured following …

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A Floristic Survey Of The Lichens Of The Spring Mountains, Nevada, Usa, Monica W. Proulx Dec 2011

A Floristic Survey Of The Lichens Of The Spring Mountains, Nevada, Usa, Monica W. Proulx

Theses and Dissertations

This thesis is the culmination of a graduate research project involving a floristic survey of the lichens of the Spring Mountain National Recreation Area (SMNRA), Humboldt-Toiyabe National Forest, Nevada. The project was based on extensive collections made between 1997 and 2007 as part of an air pollution biomonitoring program and a baseline established by Larry St. Clair (BYU). The Spring Mountains are a sky island mountain range in the Mojave Desert located less than an hour northwest of Las Vegas. A floristic survey of the lichen communities in the Spring Mountains represents a major addition to our understanding of the …

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Species Level Differences In The Ecology Of Two Neotropical Tadpole Species: Responses To Nonlethal Predators And The Roles Of Competition And Resource Use, Zacharia Costa Dec 2011

Species Level Differences In The Ecology Of Two Neotropical Tadpole Species: Responses To Nonlethal Predators And The Roles Of Competition And Resource Use, Zacharia Costa

Theses and Dissertations

Closely related species at the same trophic level are often considered to be ecologically equivalent. However, it is clear that individuals species can have unique functional roles that drive community and ecosystem processes. In this study we examine the growth responses of two Neotropical hylid tadpole species, Agalychnis callidryas and Dendropsophus ebraccatus, to intraspecific and interspecific competition. We also look at density-dependent effects of each on phytoplankton, periphyton and zooplankton, as well as their responses to a caged dragonfly predator through ontogeny. Intraspecific competition affected both species similarly, and their effects on resources were qualitatively similar but quantitatively different. Predators …

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Evaluation Of Brook Trout (Salvelinus Fontinalis) Introductions And Re-Introductions Into Four Virginia Blue Ridge Mountain Streams, Michael Isel Iii Dec 2011

Evaluation Of Brook Trout (Salvelinus Fontinalis) Introductions And Re-Introductions Into Four Virginia Blue Ridge Mountain Streams, Michael Isel Iii

Theses and Dissertations

Approximately 100 brook trout were transplanted into each of four Virginia streams in September 2008. Garth Run and Kinsey Run were re-introductions, and Wildcat Hollow and Sweet Run were new introductions. Single pass electrofishing (EF) surveys were conducted with a backpack electrofisher five times during the study. Selected trout > 70 mm but < 100 mm and all trout > 100 mm received a Biomark® 134.2 kHz passive integrated transponder (PIT) tag to identify individual fish upon recapture. Trout were present in all streams almost three years post introductions. Catches decreased across the first four surveys. Young of year catch rates severely decreased from June 2009 (n = …

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Factors Controlling Dissolved Organic Carbon Lability And Ecological Fate In The East Branch Swift River, Massachusettes, Hall Eric Dec 2011

Factors Controlling Dissolved Organic Carbon Lability And Ecological Fate In The East Branch Swift River, Massachusettes, Hall Eric

Theses and Dissertations

Fluvial systems have been estimated to transform, transport, or store 2.75 petagrams (Pg) of Organic Carbon (OC) per year. Although approximately 1Pg per year of terrestrial carbon is fluxed to the atmosphere through inland waters, little is known about the factors regulating its eventual ecological fate. 28 day lability incubations were conducted concurrent with the measurement of several environmental parameters including discharge, nutrient concentration, DO13C, and DOC:DON at several sites along Bigelow Brook and the East Branch of the Swift River, Massachusetts. Temporal and spatial variation of DOC, DOC:DON and DO13C were explored. Two distinct DOC consumption rates, short and …

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Shrubs As Sentinels Of Ordnance Contamination: Using Plant Physiology And Remote Sensing To Detect Tnt In Soils, Kathryn Rubis Nov 2011

Shrubs As Sentinels Of Ordnance Contamination: Using Plant Physiology And Remote Sensing To Detect Tnt In Soils, Kathryn Rubis

Theses and Dissertations

Methods for rapid, safe and effective detection of unmapped buried ordnance are vital to the protection of humans and environmental quality throughout the world. This study aimed to investigate the use of phytosensing and to understand the physiological response of woody plants to 2,4,6-trinitrotoluene (TNT) contamination. Baccharis halimifolia were potted in soils containing various concentrations of TNT and physiological responses were observed over a 9-week experimental period. Measurements included the collection of remotely sensed data, such as hyperspectral reflectance and chlorophyll fluorescence, and traditional plant-level physiological data. In accordance with the hypothesis, low levels of TNT improved physiological response in …

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Composition Of Suspended And Benthic Particulate Matter In The Tidal Freshwater James River, Anne Schlegel Sep 2011

Composition Of Suspended And Benthic Particulate Matter In The Tidal Freshwater James River, Anne Schlegel

Theses and Dissertations

Investigating linkages between the compositions of suspended (seston) and benthic particulate matter is important to the understanding of organic matter (OM) cycling and nutrient retention in aquatic systems. We compared the quantity and quality of the truly suspended (TS) and settleable (SB) fractions of seston as well as benthic particulate matter in the tidal freshwater James River, Virginia. The mass of seston and OM was consistently higher in the TS fraction compared to the SB fraction. OM was preferentially retained in the TS fraction relative to seston. The proportional contribution of OM constituents (chlorophyll a, particulate organic carbon and nitrogen) …

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Analyses Of Sorex Longirostris Distribution In Arkansas And Across The Mississippi River, Garrett Adam Mikel Sep 2011

Analyses Of Sorex Longirostris Distribution In Arkansas And Across The Mississippi River, Garrett Adam Mikel

Theses and Dissertations

The southeastern shrew (Sorex longirostris) is considered uncommon and a Species of Greatest Conservation Need in Arkansas, exhibiting an apparent gap in eastern Arkansas. Soricinae are exceptionally small and short-lived with limited dispersal, making them especially prone to speciation through long-term zoogeographic barriers to gene flow consistent with phylogeographic category 1. Therefore, I compiled Arkansas occurrences, evaluated persistence at previous capture sites in the state, surveyed additional counties, quantified microhabitat at my capture locations, and evaluated systematic status of S. longirostris east and west of the Mississippi River using mitochondrial DNA. Number of documented specimens in Arkansas has increased to …

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Legacy Sediments In Streams - Effects On Nutrient Partitioning During Simulated Re-Suspension Events., Molly Sobotka Aug 2011

Legacy Sediments In Streams - Effects On Nutrient Partitioning During Simulated Re-Suspension Events., Molly Sobotka

Theses and Dissertations

Anthropogenic inputs of nutrients and sediment are a widespread problem in U.S. streams causing localized impairment and contributing to eutrophication of coastal habitats. Sediments and dissolved nutrients interact through diverse processes including ion exchange, sorption and biotic assimilation by particle-bound bacteria. This study examined the effects of sediment re-suspension on nutrient partitioning in lab microcosms using fine benthic matter collected from two Virginia Coastal Plain streams. Kimages Creek was recently restored following dam removal and was characterized by large deposits of legacy sediments. Courthouse Creek was characterized by sandy substrates typical of Coastal Plain streams. Sediment characteristics differed between the …

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The Abundance And Infection Status Of Anopheles Spp. Mosquitoes At Three Sites In Loudoun County, Northern Virginia, Priya Krishnan Aug 2011

The Abundance And Infection Status Of Anopheles Spp. Mosquitoes At Three Sites In Loudoun County, Northern Virginia, Priya Krishnan

Theses and Dissertations

Malaria is a re-emerging infectious disease with approximately half of the world's population at risk. In the US, since the 1950’s the Center for Disease Control (CDC) has been reporting between 1,000 and 1,500 cases of malaria every year. A majority of these cases were among US travellers and were attributed to Plasmodium falciparum. In August 2002, two cases of human malaria due to Plasmodium vivax were reported in Loudoun County, Northern Virginia. The Center for Disease Control and Prevention concluded that these cases were acquired locally. This was because of an absence of other risk factors such as international …

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Characterizing The Distribution Of Planktonic Fecal Bacteria In The James River, Richmond, Virginia, John Furry Aug 2011

Characterizing The Distribution Of Planktonic Fecal Bacteria In The James River, Richmond, Virginia, John Furry

Theses and Dissertations

Surface waters containing fecal bacteria present significant public health risks. Understanding the sources of and factors affecting the distribution of fecal-indicating bacteria is necessary to predict potential illnesses more effectively. This thesis presents two studies on the distribution of fecal bacteria in the James River through Richmond, Virginia. Chapter 1 describes nearly 11 years of water quality, climate, and hydrologic data that occurred with changes in Escherichia coli concentrations, concluding that Richmond contributes significant quantities of fecal bacteria to the James River, and that the distribution of these bacteria varies seasonally. Chapter 2 details the development of Polymerase Chain Reaction …

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Morphology, Material And Vibratory Properties Of The Swimbladder In The Carp, Cyprinus Carpio, Yasha Mohajer Jul 2011

Morphology, Material And Vibratory Properties Of The Swimbladder In The Carp, Cyprinus Carpio, Yasha Mohajer

Theses and Dissertations

The carp Cyprinus carpio has a two-chambered swimbladder and excellent hearing. I explored the hypothesis that the anterior chamber, which connects to Weberian ossicles, is adapted for hearing by testing both chambers for material properties. I also determined displacement and auditory responses to mechanical strikes. Wall stress is higher in the posterior, strain in the anterior and modulus lower in the anterior chamber. Strikes increase pressure followed by a variable rebound that rapidly decays. Displacement and sound amplitude increase with hammer force, and amplitude is similar in both chambers for within chamber strikes but lower across chambers. Normalized for equivalent …

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Novel Methodology For Assessing Phytoplankton Response To Pco2 Enrichment In Fresh And Saltwater, Susan B. Gifford Jul 2011

Novel Methodology For Assessing Phytoplankton Response To Pco2 Enrichment In Fresh And Saltwater, Susan B. Gifford

Theses and Dissertations

Atmospheric CO2 emissions are on the rise and are expected to reach 780 parts per million by the year 2100. Research investigating the impacts of increasing CO2 is a relatively new field and the response of phytoplankton communities is largely unknown, especially in coastal and freshwater ecosystems where no CO2 manipulation studies have completed. The present study attempts to encourage uniformity in methods utilized in CO2 perturbation studies and identifies changes in phytoplankton abundance in freshwater (James River) and coastal ocean (Atlantic, Cape Hatteras) sites. A novel bubbling method to manipulate pCO2 was compared with the classic method of acid …

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Investigation Of Pre- And Post-Zygotic Reproductive Barriers Between Two Host-Plant Complex Races Of The Parasitic Wasp Cotesia Congregata (Say) [Hymenoptera: Braconidae], Justin Bredlau Jul 2011

Investigation Of Pre- And Post-Zygotic Reproductive Barriers Between Two Host-Plant Complex Races Of The Parasitic Wasp Cotesia Congregata (Say) [Hymenoptera: Braconidae], Justin Bredlau

Theses and Dissertations

Investigations of host-associated differentiation of parasitoids have largely focused on the degree of molecular genetic differentiation, but a true test of species status must examine the mating patterns of differentiated populations to determine if they can interbreed in the wild and produce viable offspring. We examined possible mechanisms of isolation between two genetically distinct host-plant complex races of the braconid, Cotesia congregata, originating from hosts on tobacco and catalpa. We compared male responses to female pheromones, elements of male acoustic courtship signals, and breeding success between the two races. Males responded to pheromones from both sources and male courtship signals …

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An Invasive Species Reduces Aquatic Insect Flux To Terrestrial Food Webs, Steven S. Merkley Jul 2011

An Invasive Species Reduces Aquatic Insect Flux To Terrestrial Food Webs, Steven S. Merkley

Theses and Dissertations

Although it is well documented how introduced species can negatively affect native species, we only poorly understand how they may alter ecosystem functions. We investigated how an invasive fish affected the flux of aquatic insects to terrestrial food webs using mesocosms in a desert spring ecosystem. We compared aquatic insect emergence between alternative community states with monocultures and polycultures of two native species of fish, least chub (Iotichthys phlegethontis) and Utah chub (Gila atraria) plus, introduced western mosquitofish (Gambusia affinis). We tested three hypotheses: (1) aquatic insect biomass will be greater than terrestrial insect …

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Changes In Life History Within An Individual's Lifetime, Eric J. Billman Jul 2011

Changes In Life History Within An Individual's Lifetime, Eric J. Billman

Theses and Dissertations

A central goal of life history theory is to understand the selective factors that generate the diversity of reproductive patterns observed in nature. Within lifetime changes in reproductive investment will determine an organism's fitness; however, this area of life history theory has received less attention than comparisons among population that characterize life history traits as a single population mean. Reproductive allocation can be affected by multiple cues; the integration of these cues across an organism's lifetime generates the diversity in life history strategies observed in nature. Life history studies should examine the interacting effects of multiple cues on life history …

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Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost May 2011

Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost

Theses and Dissertations

It is important to understand mechanisms that facilitate expansion of two common shrubs, Morella cerifera and Baccharis halimifolia in coastal environments. The purpose of my study was to investigate the physiological and structural changes that occur as leaves age. Photosynthesis, incident light, chlorophyll, and leaf C:N ratios were quantified for young, intermediate, and old leaves (distal, central and proximal leaves, respectively). Leaf structural differences were also compared. Leaves did not change morphologically with age. Light decreased with leaf age and during winter months. Photosynthesis showed no seasonal or age related patterns. Chlorophyll increased initially and then declined with age due …

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Exploring The Functional Interaction Between Camk-Ii And P53, Raymond Lai Apr 2011

Exploring The Functional Interaction Between Camk-Ii And P53, Raymond Lai

Theses and Dissertations

Calcium (Ca2+)/calmodulin-dependent kinase 2 (CaMK-II) is a multifunctional member of a family of Ca2+/calmodulin-dependent serine/threonine protein kinases that respond to transient intracellular calcium signaling. CaMK-II has been reported to be involved with transcription regulation, cell motility, neuronal development, cell cycle regulation, and more recently early development of vertebrates (Easley et al., 2008; Rothschild et al., 2009; Francescatto et al., 2010). Through previous work in the lab using tandem mass spectrometry and “substrate-trapping mutants”, tumor suppressor protein 53 (p53) was identified as a novel CaMK-II binding partner in tissue culture. In this study, I sought to provide characterization of the functional …

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Species Trees And Species Delimitation With Multilocus Data And Coalescent-Based Methods: Resolving The Speciation History Of The Liolaemus Darwinii Group (Squamata, Tropiduridae), Arley Camargo Bentaberry Feb 2011

Species Trees And Species Delimitation With Multilocus Data And Coalescent-Based Methods: Resolving The Speciation History Of The Liolaemus Darwinii Group (Squamata, Tropiduridae), Arley Camargo Bentaberry

Theses and Dissertations

The inference of species boundaries and phylogenetic relationships are fundamental for evolutionary, ecological, and conservation studies. The resolution of species boundaries and the inference of phylogenetic relationships among species are required to define the units of analysis and to find the most closely related units for evaluating alternative models of speciation. I highlight lizards as model organisms for ecological and evolutionary studies, emphasizing their contributions to advances in understanding linkages between phylogeography and speciation. In this dissertation, I focus on the phylogenetic relationships of the lizards in the Liolaemus darwinii group, and the species boundaries of a nested clade within …

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Morphometric And Genetic Variation Among Populations Of The Southern Short-Tailed Shrew, Blarina Carolinensis, Located Along The Coastal Plain Of Virginia, Devon Kersten Jan 2011

Morphometric And Genetic Variation Among Populations Of The Southern Short-Tailed Shrew, Blarina Carolinensis, Located Along The Coastal Plain Of Virginia, Devon Kersten

Theses and Dissertations

The distribution of short-tailed shrews, Blarina carolinensis and B. brevicauda, demonstrates contiguous allopatry in peninsular situations in the Coastal Plain of Virginia, and in other areas. The distribution of these two species is unusual in that they do not exhibit syntopy except within a narrow corridor along the borders of their ranges. Interestingly, along the Coastal Plain of Virginia, B. carolinensis is generally found only at the distal ends of the peninsular areas, existing as local populations that appear to be isolated from each other and from the primary population that exists in south-central Virginia. It is thought that the …

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Determining Impediments To Gene Flow In A Natural Population Of Cornus Florida L. Cornaceae, Using Integrative Landscape Genetic Techniques, Crystal Meadows Jan 2011

Determining Impediments To Gene Flow In A Natural Population Of Cornus Florida L. Cornaceae, Using Integrative Landscape Genetic Techniques, Crystal Meadows

Theses and Dissertations

This study examined the impact intervening environment has on gene flow in the insect pollinated understory tree, Cornus florida L., by combining GIS and landscape genetic techniques (Least Cost Path Analysis, Circuit Theory, and Conditional Genetic Distance). Traditional population genetic analysis indicated pair-wise relatedness was significantly correlated to distance (Pearson; r = -0.312, P < 0.001) suggesting a spatial component to offspring relatedness. Dispersal throughout the study site was non-random, exhibiting a high degree of pollen pool structure due to restricted gene flow (Two-Generation Analysis; Φft = 0.161, P = 0.001). Forest structure was quantified in GIS layers representing coniferous canopies, mixed hardwood canopies, C. florida canopies, open understory (roads), and open understory/canopy due to tree removal. Of these layers, landscape isolation for the roads layer provided the best-fit model for describing genetic differentiation among sampled pollen pools (Mantel; r = 0.542, P = 0.001). These data also suggest that improved biological inferences can be gained by examining a range of landscape isolation models.

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Head-Start Juvenile And Adult Resident Eastern Box Turtles (Terrapene Carolina Carolina): Winter Ecology Including Microhabitat Selection, Temperature Tolerance And Philopatry, Amberly Moon Jan 2011

Head-Start Juvenile And Adult Resident Eastern Box Turtles (Terrapene Carolina Carolina): Winter Ecology Including Microhabitat Selection, Temperature Tolerance And Philopatry, Amberly Moon

Theses and Dissertations

The Eastern box turtle (Terrapene carolina carolina) is one of the most common reptiles in North America, but is soon to be threatened due to increased urbanization, disease, and the pet and food trades. In order to assist resource managers in choosing suitable sites for relocation studies, more information on the winter ecology of this species is necessary. We examined the temperature tolerance, microhabitat and degree of philopatry to hibernacula for juvenile and adult E. box turtles for two consecutive winters in Charles City Co, VA. The turtles were tracked via radio telemetry to record point locations during the active …

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Distribution And Molecular Analysis Of Avian Malaria Vectors On Four Central Virginia Prothonotary Warbler (Protonotaria Citrea) Breeding Sites, Catherine Wallace Dec 2010

Distribution And Molecular Analysis Of Avian Malaria Vectors On Four Central Virginia Prothonotary Warbler (Protonotaria Citrea) Breeding Sites, Catherine Wallace

Theses and Dissertations

Avian malaria is a devastating disease that has decimated numerous bird species. This study sought to identify the vectors of avian malaria at four central Virginia Prothonotary warbler breeding sites. Twenty one thousand mosquitoes were collected and Culex salinarius, Cx. erraticus, and Cx. pipiens/restuans were found to be the dominant species at these sites. Geographic factors, such as crop land and forest type, were determined to be potential indicators for species abundance variation between sites. Of the mosquitoes collected, ninety one (0.4%) were identified as blood fed. The blood fed mosquitoes were found to have fed on avian, mammalian, amphibian, …

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Gene Flow And Dispersal Of The Flatworm, Polycelis Coronata: A Multiscale Analysis, Jeffrey N. Moore Dec 2010

Gene Flow And Dispersal Of The Flatworm, Polycelis Coronata: A Multiscale Analysis, Jeffrey N. Moore

Theses and Dissertations

We determined genetic variance and gene flow across multiple scales (reaches, headwater segments, and catchments) to examine the dispersal ability of the flatworm Polycelis coronata along the Wasatch Mountains of Utah. Multiple models predict patterns of genetic differentiation in stream invertebrates based on dispersal traits and the spatial connectivity of the habitat. The stream hierarchy model predicts genetic differentiation to be low and gene flow to be high between reaches nested in segments, moderate among segments within catchments, and differentiation to be highest and gene flow lowest among catchments, whereas the headwater model predicts the greatest differentiation between headwater segments. …

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Depth And Time Related Variations Of Microbial Communiites In An Emergent Freshwater Wetland, Amy Jenkins Dec 2010

Depth And Time Related Variations Of Microbial Communiites In An Emergent Freshwater Wetland, Amy Jenkins

Theses and Dissertations

Soils, and the microbial communities contained within them, are vital for most chemical, physical, and biological processes. This study investigated how microbial community structure responded to environmental changes, such as hydrology, across vertical space (depth) and time in an emergent fresh water wetland. Research was conducted in a non-tidal freshwater wetland along the James River (Charles City County, Virginia) by establishing plots in two areas that experienced different hydrologic regimes and plant communities. Soil cores (30 cm) were collected monthly from January 2008 to February 2009, and then every two to three months thereafter until October 2009, for a total …

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Antimicrobial And Anticancer Activity Of Essential Oils From Guatemalan Medicinal Plants, Andrew B. Miller Nov 2010

Antimicrobial And Anticancer Activity Of Essential Oils From Guatemalan Medicinal Plants, Andrew B. Miller

Theses and Dissertations

Guatemalan medicinal plants were collected and screened for the presence of essential oils using steam distillation. Oil was found in 63 species from 24 families and was tested in tube dilution assays for activity against Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Lactobacillus acidophilus and Candida albicans. Several essential oils were highly active with 20 instances of oils inhibiting the microbes at an MIC of 0.31 µl/ml. Oils were also tested against cancerous and established cell lines using a 15% (v/v) agar-media which was developed to improve essential oil solubility. Assays were performed against three cancer lines: …

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Site Fidelity And Population Structure Of A Solitary Subterranean Rodent, Geomys Breviceps, In Southwestern Arkansas., Kimberly Nicole King Sep 2010

Site Fidelity And Population Structure Of A Solitary Subterranean Rodent, Geomys Breviceps, In Southwestern Arkansas., Kimberly Nicole King

Theses and Dissertations

From October 2007 to April 2010, 87 Geomys breviceps were captured a total of 156 times on a 2-ha plot in southwestern Arkansas. Individuals were captured using the Sikes-Finley pocket gopher trap and all new captures were marked with passive integrated transponder (PIT) tags. Spatial distribution and movement patterns were examined using ArcGIS. The population was female biased. Average duration between initial capture and final recapture of individuals was 8 months. An individual male and female captured at the onset of the study were recaptured after 29 months and remained within 46 m of their initial capture site. Males were …

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