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Arsenite Resistance Of Euglena Mutabilis, Nicole Loumarinett Rosendo Mercado, Doug G. Cole (Mentor) 2017 University of Idaho

Arsenite Resistance Of Euglena Mutabilis, Nicole Loumarinett Rosendo Mercado, Doug G. Cole (Mentor)

Idaho Conference on Undergraduate Research

Euglena are photosynthetic unicellular protozoa. Commonly found in rivers, lakes and ponds, some Euglena are found in toxic environments, like areas of acid mine drainage where they can grow at low pH and in the presence of heavy metals and metalloids such as arsenite (e.g. Euglena mutabilis). The goal of this research is to determine if an Idaho Euglena isolate (SG6) belongs to the E. mutabilis species and to compare it’s level of arsenite resistance with other E. mutabilis strains. As part of the methodology, we have developed microtiter plate assays in which the cells are grown in ...


Supplemental Data, Russell J. Ingram, Foster Levy, Cindy L. Barrett, James T. Donaldson 2017 University of Georgia

Supplemental Data, Russell J. Ingram, Foster Levy, Cindy L. Barrett, James T. Donaldson

ETSU Faculty Works

No abstract provided.


The Role Of Gpx-8 In Dna Repair Of C. Elegans, Grant T. Read 2017 University of Iowa

The Role Of Gpx-8 In Dna Repair Of C. Elegans, Grant T. Read

University of Iowa Honors Theses

Double-stranded breaks are necessary for the resolution of crossovers during the heterotypic cell division of meiosis I. Failure to repair these DSBs can lead to programmed cell death, or apoptosis. Caenorhabditis elegans, a member of the phylum Nematoda, is a model organism for the study of meiosis due to the temporal-spatial pattern of its gonad. gpx-8, homologous to human gpx-4, codes for a member of the glutathione peroxidase family, a group of proteins involved in the detoxification of peroxides. This project examined the effects of a homozygous deletion of the gpx-8 gene on the C. elegans germ line. The primary ...


Factors Influencing Swallow Bug (O. Vicarius) Populations Within Cliff Swallows Nests, Paul McPhail 2016 University of Northern Colorado

Factors Influencing Swallow Bug (O. Vicarius) Populations Within Cliff Swallows Nests, Paul Mcphail

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

Hematophagous ectoparasites such as swallow bugs (Oeciacus vicarius) have been shown to have a profound negative impact on infested bird chicks, and one study shows that O. vicarius populations are positively correlated with large colonies. In this study, we investigated the abundance of O. vicarius and other arthropods within Cliff Swallow nests, and performed statistical analysis of the results to find any variables that correlated with O. vicarius population size. We expected the number of O. vicarius would be positively influenced by urban surroundings and large Cliff Swallow colony size, and that samples collected in the fall would be larger ...


The Association Between Oxidative Stress, Cellular Differentiation And Galectins In Human Promyelocytic Leukemia Cells (Hl-60), James R. Vinnai 2016 The University of Western Ontario

The Association Between Oxidative Stress, Cellular Differentiation And Galectins In Human Promyelocytic Leukemia Cells (Hl-60), James R. Vinnai

Electronic Thesis and Dissertation Repository

Galectins are a group of β-galactoside-binding proteins involved in different cellular processes including stress responses and differentiation. The role and expression of galectins under oxidative stress and during neutrophilic differentiation was examined in HL-60 cells. Galectin gene (LGALS), and galectin protein expression were determined using RT-qPCR and immunoblotting, respectively. Neutrophilic differentiation was measured via a spectrofluorometric assay. DNA methylation and JNK signaling were investigated as galectin regulatory mechanisms. Menadione-induced oxidative stress, DMSO-induced differentiation, DNA hypomethylation and JNK signaling all promoted similar galectin expression profiles. Antioxidant N-acetylcysteine attenuated the menadione-induced galectin expression but only partially attenuated DMSO-induced galectin expression. Galectin inhibitory ...


Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski 2016 University of Texas at Tyler

Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski

Biology Theses

Habitat suitability modeling using the software package MaxEnt (Phillips, Anderson, & Schapire, 2006) is a popular method for describing the habitat of rare species. MaxEnt uses “presence only” data to develop models; however presence data are highly skewed towards areas of high detection probability and these areas may not represent the full range of habitat use. Thusly, predictions from models developed using only data from areas with high detection probability may not represent all suitable habitat. This study tested the ability of MaxEnt models developed using three different data sets to accurately describe Western Massasauga (Sistrurus t. tergeminus) habitat at a local scale. Models were evaluated by their ability to predict high suitability values at locations of known snake occurrence. The first ...


Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos 2016 University of Maine - Main

Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos

Electronic Theses and Dissertations

Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because clearance-rate measurements are affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis, calculated using a direct method based ...


An Ecological Assessment Of Wetlands Using Reference Sites., Siobhan Fennessy 2016 Selected Works

An Ecological Assessment Of Wetlands Using Reference Sites., Siobhan Fennessy

Siobhan Fennessy

No abstract provided.


Standardized Monitoring Protocols And Performance Standards For Wetland Creation, Enhancement And Restoration, Siobhan Fennessy 2016 Selected Works

Standardized Monitoring Protocols And Performance Standards For Wetland Creation, Enhancement And Restoration, Siobhan Fennessy

Siobhan Fennessy

A condition-based approach to assessing functional replacement for wetland mitigation has been developed using a reference wetland data set of natural wetlands that includes data from the major wetland types that span a gradient of human disturbance. From this data set wetland program tools were developed 1) multimetric biological indices (IBIs) and hydrological and biogeochemical indicators; 2) a rapid (conditionbased) wetland assessment tool (Ohio Rapid Assessment Method for Wetlands); and 3) a wetland classification scheme based on landscape position and dominant vegetation that accounts for variability in ecosystem processes (functions) and ecological services (values) of different types of natural wetlands ...


Biogeochemical And Hydrological Investigations Of Natural And Mitigation Wetlands., Siobhan Fennessy 2016 Selected Works

Biogeochemical And Hydrological Investigations Of Natural And Mitigation Wetlands., Siobhan Fennessy

Siobhan Fennessy

We performed a comprehensive investigation of the biota (structure) and biogeochemical cycles (processes or functions) of a population of natural (n = 9) and mitigation wetlands (n = 10). Intensive data were collected on various wetland ecosystem components including: hydrology, soil and water chemistry, characteristics of the plant, macroinvertebrate and amphibian communities, biomass production, decomposition, and nutrient cycles. The goals of the project were as follows: 1) to demonstrate the efficacy of floral and faunal community-based indicators in order to assess the performance of mitigation wetlands, 2) determine the links between floral and faunal community structural attributes and ecosystem processes in natural ...


Assessing Wetland Ecological Condition In The Cuyahoga River Watershed., Siobhan Fennessy 2016 Selected Works

Assessing Wetland Ecological Condition In The Cuyahoga River Watershed., Siobhan Fennessy

Siobhan Fennessy

We used an assessment approach combining the USEPA EMAP probabilistic sampling design with existing Ohio wetland assessment tools, including the Ohio rapid assessment method (ORAM), the modified Penn State Stressor Checklist, the Vegetation IBI and the Amphibian IBI, along with a landscape analysis (the Landscape Development Intensity Index) to evaluate the ecological condition of wetlands in the 1,300 km2 Cuyahoga River watershed. Sample sites were selected using the Generalized Random Tesselation Stratified (GRTS) survey design, which provides a geospatially balanced, stratified random sample. The Ohio Wetland Inventory was used as the sample frame for the population of wetlands in ...


Antibacterial And Antifungal Properties Of Medicinal Plants, Victoria Q. Nguyen 2016 Loyola Marymount University

Antibacterial And Antifungal Properties Of Medicinal Plants, Victoria Q. Nguyen

Research & Exhibition

Medicinal plants have long been used to treat many different conditions and have recently become more popular as a “re-emerging health aid” due to the rising costs of prescription drugs. The various chemicals and compounds that are beneficial to the plants themselves may potentially offer health benefits to humans as well. Antibacterial and antifungal properties are particularly applicable to human health as many diseases are the result of bacterial and fungal infections. Because plants often come into contact with bacteria and fungi (some of which could be potentially harmful), antibacterial and antifungal properties are fairly common amongst plants, albeit with ...


Assessing Competition Between Invasive And Native Plant Species At Ascot Hills Park, Jacquelyn Galvez 2016 Loyola Marymount University

Assessing Competition Between Invasive And Native Plant Species At Ascot Hills Park, Jacquelyn Galvez

Research & Exhibition

No abstract provided.


Effect Of Arginine On Oligomerization And Stability Of N-Acetylglutamate Synthase., N Haskins, A Mumo, P H Brown, Mendel Tuchman, Hiroki Morizono, L Caldovic 2016 George Washington University

Effect Of Arginine On Oligomerization And Stability Of N-Acetylglutamate Synthase., N Haskins, A Mumo, P H Brown, Mendel Tuchman, Hiroki Morizono, L Caldovic

Integrative Systems Biology Faculty Publications

N-acetylglutamate synthase (NAGS; E.C.2.3.1.1) catalyzes the formation of N-acetylglutamate (NAG) from acetyl coenzyme A and glutamate. In microorganisms and plants, NAG is the first intermediate of the L-arginine biosynthesis; in animals, NAG is an allosteric activator of carbamylphosphate synthetase I and III. In some bacteria bifunctional N-acetylglutamate synthase-kinase (NAGS-K) catalyzes the first two steps of L-arginine biosynthesis. L-arginine inhibits NAGS in bacteria, fungi, and plants and activates NAGS in mammals. L-arginine increased thermal stability of the NAGS-K from Maricaulis maris (MmNAGS-K) while it destabilized the NAGS-K from Xanthomonas campestris (XcNAGS-K). Analytical gel chromatography and ultracentrifugation ...


Effects Of Gut-Associated Yeasts On Drosophila Melanogaster Performance, Yanira Jiménez Padilla 2016 The University of Western Ontario

Effects Of Gut-Associated Yeasts On Drosophila Melanogaster Performance, Yanira Jiménez Padilla

Electronic Thesis and Dissertation Repository

I used Drosophila melanogaster as a model to study the role of the gut microbiota, specifically yeasts, in animal physiology. I used Saccharomyces cerevisiae, the yeast commonly included in Drosophila diet, and Lachancea kluyveri, isolated from some Drosophila in the wild, and generated axenic (germ-free) and gnotobiotic (yeast-fed) flies. I found that L. kluyveri persists in the crop, as ascospores and vegetative cells, longer than S. cerevisiae. Some L. kluyveri vegetative cells survive passage through the gut. Egg to adult development time is reduced by 14% in vials containing live L. kluyveri or S. cerevisiae, whereas heat-killed yeasts reduced development ...


Netrin-3 Peptide (C-19) Is A Chemorepellent And A Growth Inhibitor In Tetrahymena Thermophila, Matthew S. Merical, Kenneth W. Ward, Lois Parks, Heather G. Kuruvilla 2016 Cedarville University

Netrin-3 Peptide (C-19) Is A Chemorepellent And A Growth Inhibitor In Tetrahymena Thermophila, Matthew S. Merical, Kenneth W. Ward, Lois Parks, Heather G. Kuruvilla

Science and Mathematics Faculty Presentations

The netrins are a family of signaling proteins expressed throughout the animal kingdom. Netrins play important roles in developmental processes such as axonal guidance and angiogenesis. Netrin-1, for example, can act as either a chemoattractant or a chemorepellent for axonal growth cones depending upon the concentration of the protein as well as the cell type. Netrin-1 acts as a growth factor in some cell types and is expressed by some tumor cells. Netrin-3 appears to share some signaling apparatus with netrin-1, but is less widely expressed, and its physiological roles are much less understood.

Tetrahymena thermophila are free-living, eukaryotic, ciliated ...


Nonmotorized Recreation And Motorized Recreation In Shrub-Steppe Habitats Affects Behavior And Reproduction Of Golden Eagles (Aquila Chrysaetos), Robert J. Spaul, Julie A. Heath 2016 Boise State University

Nonmotorized Recreation And Motorized Recreation In Shrub-Steppe Habitats Affects Behavior And Reproduction Of Golden Eagles (Aquila Chrysaetos), Robert J. Spaul, Julie A. Heath

Julie Heath

Different forms of outdoor recreation have different spatiotemporal activity patterns that may have interactive or cumulative effects on wildlife through human disturbance, physical habitat change, or both. In western North America, shrub-steppe habitats near urban areas are popular sites for motorized recreation and nonmotorized recreation and can provide important habitat for protected species, including golden eagles. Our objective was to determine whether recreation use (i.e., number of recreationists) or recreation features (e.g., trails or campsites) predicted golden eagle territory occupancy, egg-laying, or the probability a breeding attempt resulted in ≥1 offspring (nest survival). We monitored egg-laying, hatching and ...


The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe- Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette 2016 The University of Southern Mississippi

The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe- Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette

Master's Theses

The elasmobranch osmoregulatory strategy is predicated on the accumulation of nitrogenous compounds, primarily urea and trimethylamine n¬-oxide (TMAO). Despite the abundance of these plasma osmolytes, it is notable that elasmobranchs appear to lack urease and TMA oxidase (Tmase), enzymes that scavenge urea-nitrogen and synthesize TMAO, respectively. However, urease and Tmase are found in many species of bacteria. Therefore, I hypothesized that intestinal bacteria are responsible for urease and Tmase activity in elasmobranchs. Absent dietary nitrogen sources, I evaluated the effects of reduced intestinal microbiota on osmoregulation in Atlantic stingray (Dasyatis sabina) in vivo. D. sabina were given daily broad-spectrum ...


Pharmacokinetics, Tissue Distribution, Synergistic Activity, And Antitumor Activity Of Two Isomeric Flavones, Crystal L. Whitted 2016 East Tennessee State University

Pharmacokinetics, Tissue Distribution, Synergistic Activity, And Antitumor Activity Of Two Isomeric Flavones, Crystal L. Whitted

Electronic Theses and Dissertations

Flavonoids are polyphenolic secondary metabolites found in plants that have bioactive properties including antiviral, antioxidant, and anticancer. Two isomeric flavone were extracted from Gnaphalium elegans and Achyrocline bogotensis, plants used by the people from the Andean region of South America as remedies for cancer. 5,7-dihydroxy-3,6,8-trimethoxy-2-phenyl-4H-chromen-4-one (5, 7–dihydroxy- 3, 6, 8 trimethoxy flavone/ flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-chromen-4-one (3, 5–dihydroxy-6, 7, 8–trimethoxy flavone/ flavone B) have shown antineoplastic activity against colon cancer cell lines dependent upon their differentiation status. Pharmacokinetic studies reported herein were used to determine dosing for antitumor assays, as ...


Investigation Of Lipid Profile Patterns Along Latitude In An Eastern Australian Cline And After Stress Selection In The Laboratory, And Experiments On Stress Tolerance With Rnai Knockdown Of Lipid Biosynthesis Genes, Li Ko 2016 University of Nebraska-Lincoln

Investigation Of Lipid Profile Patterns Along Latitude In An Eastern Australian Cline And After Stress Selection In The Laboratory, And Experiments On Stress Tolerance With Rnai Knockdown Of Lipid Biosynthesis Genes, Li Ko

Dissertations and Theses in Biological Sciences

Homeoviscous adaptation in membranes and changes in energy storage lipids such as triacylglycerols (TAGs) are the two main themes of adaptation to environmental conditions. Basal patterns of lipid compositional profile of Drosophila melanogaster along a latitudinal gradient in the eastern coast of Australia indicate variations of lipidome associated with climatic patterns. Lipidome data were collected for eight locations along the eastern Australian cline for both sexes in D. melanogaster and D. simulans. To further investigate the relationship between lipidome patterns and environmental factors, we utilized laboratory selection studies using stress conditions including high temperature tolerance, desiccation survival, and chill-coma recovery ...


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