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Consequences Of Shrub Encroachment: Linking Changes In Canopy Structure To Shifts In The Resource Environment, Steven Brantley

Theses and Dissertations

Shrub expansion in herbaceous ecosystems is emerging as an important ecological response to global change, especially in mesic systems where increases in canopy biomass are greatest. Two consequences of woody encroachment are increases in belowground resources, such as carbon and nitrogen, and reductions in above-ground resources such as light, which affect diversity, community trajectory, and ecosystem function. My objective was to determine how expansion of the nitrogen-fixing shrub Morella cerifera affected the resource environment across a chronosequence of shrub expansion on a Virginia barrier island. I quantified changes in carbon (C) and nitrogen (N) cycling, canopy structure and understory light …

Structural Basis For Inhibition Of Mammalian Adenylyl Cyclase By Calcium, Tung-Chung Mou, Nanako Masada, Dermot M. Cooper, Stephen R. Sprang

Biological Sciences Faculty Publications

Type V and VI mammalian adenylyl cyclases (AC5, AC6) are inhibited by Ca(2+) at both sub- and supramicromolar concentration. This inhibition may provide feedback in situations where cAMP promotes opening of Ca(2+) channels, allowing fine control of cardiac contraction and rhythmicity in cardiac tissue where AC5 and AC6 predominate. Ca(2+) inhibits the soluble AC core composed of the C1 domain of AC5 (VC1) and the C2 domain of AC2 (IIC2). As observed for holo-AC5, inhibition is biphasic, showing "high-affinity" (K(i) = approximately 0.4 microM) and "low-affinity" (K(i) = approximately 100 microM) modes of inhibition. At micromolar concentration, Ca(2+) inhibition is …

The Presence Of Amphibian Ranavirus In Virginia Warm Water Fish Hatchery Ponds, Elizabeth Nelson

Theses and Dissertations

Amphibian declines have been occurring world wide over the past several decades. Infectious disease and environmental changes have been implicated as the causative agents in these declines. Fish stocking from hatcheries provides a unique opportunity for organisms, including infectious diseases, to travel over long distances. Ranavirus was previously found in two ponds at Harrison Lake National Fish Hatchery in Charles City County, Virginia. Therefore, the primary objective of this study was to determine if ranavirus is present in tadpoles from four warm water fish hatcheries in Virginia. A secondary objective of this study was to determine if there are relationships …

Generation Of Macrophage Chemotactic Factors By Spla2, Andria Chambers

Theses and Dissertations

Removal of apoptotic cells by macrophages is required in order to prevent autoimmune responses. Previous studies have reported that group IIA secretory phospholipase A2 (sPLA2) preferentially binds to apoptotic cells and induces a chemotactic factor which promotes the migration of macrophages to apoptotic cells. Based on these observations, we hypothesized that the pool of sPLA2 trapped on apoptotic cells produces chemoattractant lipids that recruit macrophages to phagocytose the apoptotic cells. To test this hypothesis, Jurkat cells were cultured under normal conditions and induced to undergo early apoptosis through treatment with D,L-threo-dihydrosphingosine. Live and early apoptotic cells were incubated with catalytically …

The Furman Lake Restoration Plan, Wade Worthen

Furman Lake Restoration Book Gallery

A presentation with text and images providing information on the history of the Furman Lake, it's environmental health decline throughout the years, and the lake's restoration. The presentation details the Furman Lake's problems, causes of these problems, and solutions. It describes Furman's progress in the restoration project, as well as it's goals for the future.

From In-Vitro To In-Vivo: Corporate Development And Efficacy Of A Topical Hair Growth Agent Derived From Natural Extracts, Kelly Michael Glynn

Masters Theses

Androgenetic alopecia (male pattern baldness) affects up to 50% of the world’s population, propelling the development for a possible treatment. The hair follicle is influenced by several genetic and physiologic factors, which, when gone awry, lead to androgenetic alopecia. Vascular endothelial and keratinocyte growth factors are believed to be promoters of hair growth, as is inhibition of the proteasome complex. The cytokine IL-1α is also known to regulate follicle dynamics. The research objective described herein was an attempt to develop a botanical blend, which could mediate the above biomarkers, be successfully incorporated into a safe topical product and be evaluated …

Factors Affecting Dissolved Oxygen Metabolism In Coastal Plain Streams Of Virginia, Julie Frank

Theses and Dissertations

I investigated seasonal and inter-site variation in factors influencing diel dissolved oxygen (DO) metabolism at four streams in the Virginia Coastal Plain. Data were collected monthly from January to August 2008 to characterize DO metabolism (diel DO amplitude, production, respiration), incident solar radiation (PAR), dissolved nutrients, fine benthic materials (mass, C:N, Chlα) and hydrology (discharge, water transit time, transient storage). Reach-scale metabolism estimates were determined using the one-station diurnal DO technique and transit time and transient storage were determined by conservative tracer additions. Incident solar radiation was the primary determinant of DO metabolism as streams experiencing higher light levels (Herring …

Molecular Systematics Of Spiny Pocket Mice (Subfamily Heteromyinae) Inferred From Mitochondrial And Nuclear Sequence Data, Melina Crystal Williamson

Theses and Dissertations

This study aims to determine species-level relationships within the genus Heteromys, as well as generic-level relationships among members of the subfamily Heteromyinae using a phylogenetic framework. Molecular sequence data were generated from two mitochondrial genes (cytochrome b and cytochrome oxidase I) and three nuclear gene segments (β-fibrinogen, engrailed protein II, and myosin heavy chain II), and analyzed under maximum parsimony, maximum likelihood, and Bayesian optimality criteria to infer relationships. Chapter 1 focuses on the phylogenetic and taxonomic implications for Heteromys from the analyses of sequence data. Phylogenies also provided a framework for delimiting species boundaries within the wide-ranging Heteromys desmarestianus …

Coupling Of Autotrophic And Heterotrophic Plankton Food Web Components In The Tidal-Freshwater James River, Usa, Matthew Beckwith

Theses and Dissertations

Empirical studies have shown that algal- and detrital-based food web components are coupled in many pelagic systems as algal carbon enhances bacterioplankton production and growth efficiencies. Such phyto-bacterioplankton coupling impacts carbon flow through plankton food webs, yet the extent of coupling is poorly understood in systems receiving large amounts of allochthonous carbon. To investigate this issue, bacterioplankton abundance (BA) and community composition were compared to chlorophyll a concentrations and phytoplankton production in the tidal-freshwater James River (VA). BA averaged 107 cells mL-1 and was significantly related to chlorophyll a, phytoplankton production, and DOC concentrations. Analysis of DOC quality using fluorescence …

Common-Path Multimodal Optical Microscopy, Marla Tipping, Chandra S. Yelleswarapu, Sri-Rajasekhar Kothapalli, Alexey Veraksa, D.V.G.L.N. Rao

Biology Faculty Publications

We have developed a common-path multimodal optical microscopy system that is capable of using a single optical source and a single camera to image amplitude, phase, and fluorescence features of a biological specimen. This is achieved by varying either contrast enhancement filters at the Fourier plane and/or neutral density/fluorescence filters in front of the CCD camera. The feasibility of the technique is demonstrated by obtaining brightfield, fluorescence, phase-contrast, spatially filtered, brightfield + fluorescence, phase +fluorescence, and edge-enhanced+fluorescence images of the same Drosophila embryo without the need for image registration and fusion. This comprehensive microscope has the capability of providing both …

Identification Of Binding Partners Of A Novel P. Falciparum Exported Protein, Monica Zapata

Theses and Dissertations

Plasmodium falciparum is the causative agent of the most severe form of malaria. This parasite drastically modifies its host cell, the erythrocyte, to create a hospitable environment for its growth and reproduction. In order for these modifications to occur, the parasite secretes proteins into the erythrocyte. While the secretion machinery is still unknown, many secreted proteins have been found to have a hydrophobic signal sequence and a novel host-targeting signal downstream of the hydrophobic sequence. A novel P. falciparum protein has been shown to be secreted from the parasitophorous vacuole, yet it lacks both a hydrophobic signal sequence and a …

The Role Of Mitogen-Activated Protein Kinases In The Regulation Of Plant Development, Erica Satterfield

Theses and Dissertations

Mitogen-activated protein kinases are part of an evolutionarily conserved protein phosphorylation cascade which serves essential regulatory functions in eukaryotic organisms. Although the role of MAPKs in the regulation of a plant’s response to environmental stress and plant defense has been well established, very little is known about their role in the regulation of plant developmental processes. In order to examine the role of MAPKs in plant growth and development, a strong mammalian MAPK phosphatase (MKP-1), which is known to inactivate MAPKs in plants, was introduced into tobacco plants. In tobacco plants, MKP-1 overexpression altered plant responses to the phytohormones, ethylene …

Rap1 Is Essential For Silencing Telomeric Variant Surface Glycoprotein Genes In Trypanosoma Brucei, Xiaofeng Yang, Luisa M. Figueiredo, Amin Espinal, Eiji Okubo, Bibo Li

Biological, Geological, and Environmental Faculty Publications

Trypanosoma brucei expresses variant surface glycoprotein (VSG) genes in a strictly monoallelic fashion in its mammalian hosts, but it is unclear how this important virulence mechanism is enforced. Telomere position effect, an epigenetic phenomenon, has been proposed to play a critical role in VSG regulation, yet no telomeric protein has been identified whose disruption led to VSG derepression. We now identify tbRAP1 as an intrinsic component of the T. brucei telomere complex and a major regulator for silencing VSG expression sites (ESs). Knockdown of tbRAP1 led to derepression of all VSGs in silent ESs, but not VSGs located elsewhere, and …

Stem Cell Order Was Immoral And Unnecessary, Nicanor Austriaco

Theology Faculty Publications

No abstract provided.

My 20-Year Research Journey For A New Species Of Spiders, Or How To Come To A New Discovery, Vladimir Ovtcharenko

Touchstone

From time to time students ask me whether it is difficult to discover new species of organisms on our planet. To answer this question, I have decided to tell my story of how I discovered a new species of spider that I have dedicated to Eugenio María de Hostos.

Modeling Brain Injury: Expression Of Glial Fibrillary Acidic Protein In Stretch-Injured Astrocytes, Lindsey Cooke

Undergraduate Theses and Capstone Projects

Traumatic brain injury (TBI) is the leading cause of death and disability in individuals under 45. Individuals who survive TBI may be disabled for the rest of their lives and suffer from cognitive, physical, social and financial problems. Following TBI it has been shown that astrocytic gene expression of many proteins, including glial fibrillary acidic protein (GFAP), increases. These “reactive” astrocytes are thought to have both beneficial and detrimental effects on neuronal survival and function. The current study uses an in vitro model of injury which grows astrocytes on deformable silastic membranes to allow for dynamic stretch of cultured cells …

Integrated Fisheries Management. Allocation Report Roe's Abalone Resource Perth Metropolitan Region., Integrated Fisheries Allocation Advisory Committee

Fisheries Management Papers

The introduction of Integrated Fisheries Management (IFM) is a recent development in the management of fisheries in Western Australia. IFM is an initiative aimed at addressing the issue of how fish resources in Western Australia can be best shared between competing users within the broad context of “Ecologically Sustainable Development”, or ESD.

Linking Wildlife Populations With Ecosystem Change: State-Of-The-Art Satellite Ecology For National-Park Science, Mark Hebblewhite

Biological Sciences Faculty Publications

As human impacts increase in national parks and the greater ecosystems surrounding them, the National Park Service faces the difficulty of monitoring ecosystem changes and responses of key wildlife indicator species within parks. Responses of bison to trail grooming in Yellowstone National Park (Wyoming, Montana, and Idaho) and control of the animals once they leave the park (Bruggeman et al. 2007), migration of wildlife across park boundaries (Griffith et al. 2002; Berger 2004), effects of restored wolves on vegetation communities through trophic cascades (Hebblewhite et al. 2005), and responses of wildlife to the use of prescribed fires all represent problems …

Evidence For The Evolution Of Reduced Mycorrhizal Dependence During Plant Invasion, Elizabeth K. Seifert, James D. Bever, John L. Maron

Biological Sciences Faculty Publications

Introduced species inevitably experience novel selection pressures in their new environments as a result of changes in mutualist and antagonist relationships. While most previous work has examined how escape from specialist enemies has influenced herbivore or pathogen resistance of exotic species, post-introduction shifts in exotic dependence on mutualists have not been considered. In a common environment, we compared dependence on AM fungi of North American and European populations of Hypericum perforatum (St. John's Wort), a forb native to Europe. Introduced North American populations responded less to inoculation with AM fungi than did European populations. Root architecture was strongly correlated with …

The Platycerus (Coleoptera, Lucanidae) Of California, With The Recognition Of Platycerus Cribripennis Van Dyke As A Valid Species, Michael S. Caterino, M J. Paulson

Publications

Th e status of Platycerus cribripennis Van Dyke, generally treated as a synonym of P. marginalis Casey, has been unclear. Here we recognize and redescribe P. cribripennis, which is endemic to the coastal mountains of California, as a valid species due to its unique morphology. A key to the Platycerus of California is presented, and the distributions of the recognized species are discussed.

Fisheries Occasional Publication No. 67 - Review Of Fisheries Research Report (177), Aldo Steffe, Department Of Fisheries Western Australia

Fisheries Occasional Publications

To provide a review of the Research Report (177) on recreational boat-based fishing in the West Coast Bioregion during 2005/06 including: • The appropriateness of the basic creel survey design used for deriving estimates of catch, effort and catch rates for this type of fishery. • An assessment of whether the assumptions, scope and omissions were suitably identified. • The robustness of the catch estimates, and any conclusions that were included in the report, and total and seasonal recreational catch estimates. These initial terms of reference were expanded to include some discussion on issues raised by (a) the WA Fisheries …

Mojave Applied Ecology Notes Spring 2009, Russell Scofield, Michele Slaton Ph.D, Alexis Suazo, Donovan J. Craig

Mojave Applied Ecology Notes

California desert managers group, vegetation monitoring in Death Valley, undergraduate research symposium at UNLV, response of Sahara mustard to water and disturbance, JFS update

Volume 02, Joseph A. Mann, Kathryn J. Greenly, Scott E. Jenkins, Andrew E. Puckette, Daniel M. Honey, Jeffery P. Ravenhorst, Jamie Elizabeth Mesrobian, Thomas Scott, Jay Crowell, Sarah Spangenberg, Amy S. Eason, Kenny Wolfe, Liz Hale, Rachel Bouchard, Will Semonco, Carley York, Ryan Higgenbothom, Adrienne Heinbaugh, Melissa Dorton, Madeline Hunter, June Ashmore, Clark Barkley, Jay Haley

Incite: The Journal of Undergraduate Scholarship

Introduction from Dean Dr. Charles Ross

Mike's Nite: New Jazz for an Old Instrument by Joseph A. Mann

Investigation of the use of Cucumis Sativus for Remediation Of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project by Kathryn J. Greenly, Scott E. Jenkins, and Andrew E. Puckette

Development of GC-MS and Chemometric Methods for the Analysis of Accelerants in Arson Cases by Scott Jenkins

Building and Measuring Scalable Computing Systems by Daniel M. Honey and Jeffery P. Ravenhorst

Nomini Hall: A Case Study in the Use of Archival Resources as Guides for Excavation at An Archaeological Site by …

Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann

All Theses And Dissertations

Populations of the gastropod Nucella lapillus are polymorphic for shell color, with light-colored shells predominating on warmer, wave-protected shores and dark-colored shells limited primarily to cooler, wave-exposed shores. During thermal stress, darker shells attain higher body temperatures than lighter shells. These results suggest that heat stress may determine field distribution patterns. However, there is currently little evidence of physiological consequences of thermal stress in these organisms. Following the guiding hypothesis that heat stress leads to cellular energy depletion, we explored whether the central energy regulator AMP-activated Protein Kinase (AMPK) is activated by heat stress. We compared this response in both …

Functional Morphology Of The Superficial Branchial Musculature Of The Dogfish Shark, Squalus Acanthias, Roy Andermann

Honors Capstones

No abstract provided.

Investigation Of Protozoan Epibionts On Deep-Sea Nematodes, Alicia Leigh Gabriele

Honors Capstones

No abstract provided.

Fisheries Occasional Publication No. 66 - Scientific Review Of The West Coast Demersal Scalefish Fishery, Western Australia, Michael O'Neill, Department Of Fisheries Western Australia

Fisheries Occasional Publications

In December 2008 the Hon Norman Moore MLC, Minister for Fisheries Western Australia appointed two independent experts to assess separately 1) the validity of scientific advice to management and 2) options to manage recreational fishing of west coast demersal scalefish. The following review (1) assesses the validity of research outlining the status of baldchin groper (Choerodon rubescens), West Australian dhufish (Glaucosoma hebraicum) and snapper (Pagrus auratus) as described in the terms of reference. In addition to the terms of reference, an opinion was requested regarding the current appropriateness of the research advice (Wise et al 2007) and the resulting management …

Proteomic Comparison Of Entamoeba Histolytica And Entamoeba Dispar And The Role Of E. Histolytica Alcohol Dehydrogenase 3 In Virulence, Paul H. Davis, Minghe Chen, Xiaochun Zhang, C. Graham Clark, R. Reid Townsend, Samuel L. Stanley

Biology Faculty Publications

The protozoan intestinal parasite Entamoeba histolytica infects millions of people worldwide and is capable of causing amebic dysentery and amebic liver abscess. The closely related species Entamoeba dispar colonizes many more individuals, but this organism does not induce disease. To identify molecular differences between these two organisms that may account for their differential ability to cause disease in humans, we used two-dimensional gel-based (DIGE) proteomic analysis to compare whole cell lysates of E. histolytica and E. dispar. We observed 141 spots expressed at a substantially (.5- fold) higher level in E. histolytica HM-1:IMSS than E. dispar and 189 spots showing …

Seasonal Variation In Diet Of A Marginal Population Of The Hispid Cotton Rat, Sigmodon Hispidus, Lynn A. Walker, Robert K. Rose

Virginia Journal of Science

Cotton rats live in oldfields, habitats with a variety of mostly herbaceous plants. Based on other studies, the hispid cotton rat, Sigmodon hispidus, eats many kinds of herbaceous plants but grasses predominate. In contrast, our population of cotton rats ate many monocots but mostly they were not grasses. Our study sought to determine the diet of the cotton rat in eastern Virginia, near the northern limit of distribution on the Atlantic Coast. Fecal samples, collected each month during an on-going capture-mark-release demographic study of the rodent community, were analyzed using a standard method. A greater variety of foods (including …

Exercise In Space: Human Skeletal Muscle After 6 Months Aboard The International Space Station, Scott A. Trappe, David Costill, Philip M. Gallagher, Andrew C. Creer, Jim R. Peters, Harlan Evans, Danny A. Riley, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The aim of this investigation was to document the exercise program used by crewmembers (n = 9; 45 +/- 2 yr) while aboard the International Space Station (ISS) for 6 mo and examine its effectiveness for preserving calf muscle characteristics. Before and after spaceflight, we assessed calf muscle volume (MRI), static and dynamic calf muscle performance, and muscle fiber types (gastrocnemius and soleus). While on the ISS, crewmembers had access to a running treadmill, cycle ergometer, and resistance exercise device. The exercise regimen varied among the crewmembers with aerobic exercise performed ~5 h/wk at a moderate intensity and resistance …