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Modelling Non-Euclideanmovement And Landscape Connectivity In Highly Structured Ecological Networks, Chris Sutherland, Angela Fuller, J. Royle

Environmental Conservation Faculty Publication Series

1. Movement is influenced by landscape structure, configuration and geometry, but measuring distance as perceived by animals poses technical and logistical challenges. Instead, movement is typically measured using Euclidean distance, irrespective of location or landscape structure, or is based on arbitrary cost surfaces. Arecently proposed extension of spatial capture-recapture (SCR)models resolves this issue using spatial encounterhistories of individuals to calculate least-cost paths (ecological distance: Ecology, 94, 2013, 287) thereby relaxingthe Euclidean assumption. We evaluate the consequences of not accounting for movement heterogeneity whenestimating abundance in highly structured landscapes, and demonstrate the value of this approach for estimatingbiologically realistic space-use patterns …

Modelling Non-Euclideanmovement And Landscape Connectivity In Highly Structured Ecological Networks, Chris Sutherland, Angela Fuller, J. Royle

Chris Sutherland

Feather Corticosterone Reveals Effect Of Moulting Conditions In The Autumn On Subsequent Reproductive Output And Survival In An Arctic Migratory Bird, N. Jane Harms, Pierre Legagneux, H. Grant Gilchrist, Joël Bêty, Oliver P. Love, Mark R. Forbes, Gary R. Bortolotti, Catherine Soos

Integrative Biology Publications

For birds, unpredictable environments during the energetically stressful times of moulting and breeding are expected to have negative fitness effects. Detecting those effects however, might be difficult if individuals modulate their physiology and/or behaviours in ways to minimize short-term fitness costs. Corticosterone in feathers (CORTf) is thought to provide information on total baseline and stress-induced CORT levels at moulting and is an integrated measure of hypothalamic-pituitary-adrenal activity during the time feathers are grown.We predicted that CORTf levels in northern common eider females would relate to subsequent body condition, reproductive success and survival, in a population of eiders nesting in the …

Epigenetic Regulation Of Nuclear Hormone Receptor Dax-1, Michael B. Heskett

Master's Theses

DAX-1 (NR0B1) is an orphan nuclear receptor that plays a key role in the development and maintenance of steroidogenic tissue in mammals. Dax-1 is also expressed in mouse embryonic stem (ES) cells and is required to maintain pluripotency. Duplication of the X-chromosome in the region containing the NR0B1 gene results in sex reversal, and mutations in NR0B1 cause adrenal hypoplasia congenita. DAX-1 has been observed to act as a corepressor of other nuclear receptors including androgen receptor (AR), estrogen receptor (ER), and steroidogenic factor 1 (SF-1). In addition to pluripotent ES cells, DAX-1 is primarily expressed in select tissues of …

High Intralocus Variability And Interlocus Recombination Promote Immunological Diversity In A Minimal Major Histocompatibility System, Anthony B. Wilson, Camilla M. Whittington, Angela Bahr

Publications and Research

Background: The genes of the major histocompatibility complex (MHC/MH) have attracted considerable scientific interest due to their exceptional levels of variability and important function as part of the adaptive immune system. Despite a large number of studies on MH class II diversity of both model and non-model organisms, most research has focused on patterns of genetic variability at individual loci, failing to capture the functional diversity of the biologically active dimeric molecule. Here, we take a systematic approach to the study of MH variation, analyzing patterns of genetic variation at MH class IIα and IIβ loci of the seahorse, which …

In The Social Amoeba, Dictyostelium Discoideum , Density, Not Farming Status, Determines Predatory Success On Unpalatable Escherichia Coli, Susanne Disalvo, Debra A. Brock, Jeff Smith, David C. Queller, Joan E. Strassmann

Biology Faculty Publications & Presentations

Background
The social amoeba Dictyostelium discoideum interacts with bacteria in a variety of ways. It is a predator of bacteria, can be infected or harmed by bacteria, and can form symbiotic associations with bacteria. Some clones of D. discoideum function as primitive farmers because they carry bacteria through the normally sterile D. discoideum social stage, then release them after dispersal so the bacteria can proliferate and be harvested. Some farmer-associated bacteria produce small molecules that promote host farmer growth but inhibit the growth of non-farmer competitors. To test whether the farmers’ tolerance is specific or extends to other growth inhibitory …

Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Why Did The Bear Cross The Road? Comparing The Performance Of Multiple Resistance Surfaces And Connectivity Modeling Methods, Samuel A. Cushman, Jesse S. Lewis, Erin Landguth

Biological Sciences Faculty Publications

There have been few assessments of the performance of alternative resistance surfaces, and little is known about how connectivity modeling approaches differ in their ability to predict organism movements. In this paper, we evaluate the performance of four connectivity modeling approaches applied to two resistance surfaces in predicting the locations of highway crossings by American black bears in the northern Rocky Mountains, USA. We found that a resistance surface derived directly from movement data greatly outperformed a resistance surface produced from analysis of genetic differentiation, despite their heuristic similarities. Our analysis also suggested differences in the performance of different connectivity …

Mechanisms Of Condition-Specific Regulation Of Mrna Stability By Puf Proteins: From Yeast To Humans, Joseph Russo

Dissertations

RNA binding proteins regulate mRNA decay and translation, two key steps in the control of gene expression in cells. Controlling mRNA metabolism allows cells to respond rapidly to altering conditions by utilizing already available mRNA, bypassing the wait for newly transcribed mRNA. The Puf family of RNA binding proteins bind specific mRNAs through interactions with sequences located in the 3’ untranslated region (UTR). Puf proteins are conserved throughout eukaryotes and have diverse roles including stem cell maintenance, neuronal development, stress response and organelle biogenesis. In Saccharomyces cerevisiae, Puf proteins are conditionally regulated in response to the cells metabolic. Specifically, in …

Landscape Of Transposable Elements In Mycosphaerella Graminicola, Braham Dhillon, Navdeep Gill, Richard Hamelin, Stephen Goodwin

Biology Faculty Articles

Background: In addition to gene identification and annotation, repetitive sequence analysis has become an integral part of genome sequencing projects. Identification of repeats is important not only because it improves gene prediction, but also because of the role that repetitive sequences play in determining the structure and evolution of genes and genomes. Several methods using different repeat-finding strategies are available for whole-genome repeat sequence analysis. Four independent approaches were used to identify and characterize the repetitive fraction of the Mycosphaerella graminicola (synonym Zymoseptoria tritici) genome. This ascomycete fungus is a wheat pathogen and its finished genome comprises 21 chromosomes, eight …

Effect Of Allyl Isothiocyanate On Developmental Toxicity In Exposed Xenopus Laevis Embryos, John Russell Williams, James R. Rayburn, George R. Cline, Roger Sauterer, Mendel Friedman

Research, Publications & Creative Work

The pungent natural compound allyl isothiocyanate isolated from the seeds of Cru-ciferous (Brassica) plants such as mustard is reported to exhibit numerous beneficialhealth-promoting antimicrobial, antifungal, anticarcinogenic, cardioprotective, and neu-roprotective properties. Because it is also reported to damage DNA and is toxic to aquaticorganisms, the objective of the present study was to determine whether it possesses tera-togenic properties. The frog embryo teratogenesis assay-Xenopus (FETAX) was used todetermine the following measures of developmental toxicity of the allyl isothiocyanate:(a) 96-h LC50, defined as the median concentration causing 50% embryo lethality; (b) 96-h EC50, defined as the median concentration causing 50% malformations of the …

A Description Of Tolerance To Apical Meristem Damage In Wild Populations Of Arabidopsis Thaliana And Its Genetic Basis, Justin Dalrymple

Biology Theses

Since plants cannot actively avoid herbivory, they rely on two primary strategies to maintain their fitness in the face of herbivore pressure: resistance—the deterrence of herbivory via physical and chemical means—and tolerance—recuperation of aboveground mass after herbivory. Although diverse groups have been shown to be tolerant to herbivory, mechanisms of tolerance are not yet well known. There is also very little known about the ecological relevance of tolerance strategies in wild populations. In Arabidopsis thaliana, the apical meristem suppresses growth of axillary meristems to a high degree under normal conditions, but a number of axillary meristemswill grow after apical meristem …

A New Species And Synonymy Of The Neotropical Eucelatoria Townsend And Redescription Of Myiodoriops Townsend, Diego J. Inclán, John O. Stireman Iii

Biological Sciences Faculty Publications

The New World tropics represents the most diverse region for tachinid parasitoids (Diptera: Tachinidae), but it also contains the most narrowly defined, and possibly the most confusing, tachinid genera of any biogeographic region. This over-splitting of genera and taxonomic confusion has limited progress toward our understanding the family in this region and much work is needed to revise, redefine, and make sense of the profusion of finely split taxa. In a recent analysis of the Neotropical genus Erythromelana Townsend, two species previously assigned to this genus, Euptilodegeeria obumbrata (Wulp) and Myiodoriops marginalis Townsend were reinstated as monotypic genera. In the …

Ecology And Physiology Of The Pathogenic Cyanobacterium Roseofilum Reptotaenium, Laurie L. Richardson, Dina Stanic, Amanda May, Abigael Brownell, Miroslav Gantar, Shawn R. Campagna

Department of Biological Sciences

Roseofilum reptotaenium is a gliding, filamentous, phycoerythrin-rich cyanobacterium that has been found only in the horizontally migrating, pathogenic microbial mat, black band disease (BBD) on Caribbean corals. R. reptotaenium dominates the BBD mat in terms of biomass and motility, and the filaments form the mat fabric. This cyanobacterium produces the cyanotoxin microcystin, predominately MC-LR, and can tolerate high levels of sulfide produced by sulfate reducing bacteria (SRB) that are also associated with BBD. Laboratory cultures of R. reptotaenium infect coral fragments, suggesting that the cyanobacterium is the primary pathogen of BBD, but since this species cannot grow axenically and Koch’s …

Model-To-Data Comparisons Reveal Influence Of Jellyfish Interactions On Plankton Community Dynamics, Kevin P. Crum, Heidi L. Fuchs, Paul Bologna, John Gaynor

Department of Biology Faculty Scholarship and Creative Works

Taxonomic shifts can alter predator feeding preference and modify ecosystem dynamics through top-down control. In Barnegat Bay-Little Egg Harbor Estuary (New Jersey, USA), sea nettle Chrysaora quinquecirrha abundances have increased in the northern portions of the estuary. We evaluated the geographical variation in top-down influence of C. quinquecirrha on plankton community dynamics. We simulated a range of jellyfish- to copepod-dominated ecosystems using a size-resolved nutrient-phytoplankton-zooplankton (NPZ) model. Zooplankton feeding was parameterized as a community average based on predator-prey size ratios and breadth of prey sizes of dominant species. We compared model outputs to data collected in the estuary during 2 …

Determining The Critical Window Of Influence Of Pcb Perinatally On Behavioral And Hormonal Development In Sprague-Dawley Rat Pups, Natalie Sommerville, Lee A. Meserve, Howard C. Cromwell

Honors Projects

Polychlorinated biphenyls (PCB) had widespread use in the United States in commercial manufacturing in the United States until the late 1970s. Even though they were banned, measurable amounts can still be found in the environment and food sources. PCB has known effects on altering hormone development and behavior in the species Rattus norvegicus. To determine the most crucial developmental time of exposure to PCB in Sprague-Dawley rat pups, rat pups were exposed to PCB at differing weeks of either gestation period or the first postnatal week. Behavioral tests were performed for the different rat pups, as well as blood …

The Role Of Lis1 In Adult Mammalian System, Xu Gao

Theses and Dissertations

Lis1 haploinsufficiency in humans results in a “smooth brain” phenotype called lissencephaly, and also causes severe cognitive and motor impairments and epilepsy. Seizure severity and frequency typically worsens with time; patients often die within the first decade due to seizure-induced aspiration and pneumonia. Various mouse models have been used to examine the role of Lis1 during brain development, and it is clear that Lis1 regulates a microtubule motor, cytoplasmic dynein. Intriguingly, Lis1 expression remains high in adult brains indicating that it plays a role in mature systems. Indeed, our group found that Lis1 and several related proteins regulate dynein-dependent axon …

Understanding The Evolutionary History Of Biochemical Innovation, Madeline Opal St. Julien

Theses and Dissertations

The serine protease (SP) gene family is an ecologically important gene family because of observed involvement in innate immunity, digestive processes, and embryological development of arthropods. In the past decade, all genes of the serine protease family have been classified in a number of arthropods, with the exception of crustacean. Possible evolutionary mechanisms have been observed based off of varying selectional pressures acting on recent SP expansions in respect to varying diets. Daphnia is the first crustacean to have its genome sequenced, and their genomes were analyzed in this study to elucidate the expansion and divergence of the SP gene …

Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad

Theses and Dissertations

Population connectivity, particularly in open systems, is an important metric for understanding population-level processes on both ecological and evolutionary timescales. In coastal marine systems, adults are typically sedentary and dispersal occurs primarily during a larval stage when individuals are transported in ocean currents. Because coastal marine populations exist as networks of interconnected subpopulations, variation in the magnitude and extent of population connectivity can have profound effects on population dynamics and species distribution limits. Connectivity is a complex process, affected by a multitude of factors, including adult inputs and physical dispersal, which operate at multiple scales and may interact. This dissertation …

The Roles Of Gsk-3ss And Apc In Cytoplasmic Dynein Regulation, Feng Gao

Theses and Dissertations

Dynein is a microtubule minus-end directed molecular motor, participating in a broad range of cellular functions, such as organelle transport, cell migration and mitosis. Dynein dysfunction is linked to many diseases including ALS, schizophrenia, Alzheimer’s disease, Parkinson’s disease and cancer. The mechanism of dynein regulation is largely unknown. We have provided evidence that glycogen synthase kinase 3β (GSK-3β) directly regulates dynein in both neurons and non-neuronal cells. GSK-3β interacts with and phosphorylates dynein in vitro. Dynein phosphorylation by GSK-3β reduces its interaction with Ndel1, a regulator contributing to dynein force generation. Dynein motility is stimulated both by pharmacological GSK-3β inhibitors …

Global Climate Change And The Southern Ocean: How Antarctic Fishes Physiologically Respond To A Changing Environment From The Cellular To The Organismal Level, Laura A. Enzor

Theses and Dissertations

Studies have projected that future changes in sea surface temperature and pCO2 levels will impact higher latitudes to a greater extent than in temperate regions. For notothenioid fishes of the Southern Ocean, evolution in extremely stable, cold waters has resulted in several adaptations which have left these fishes poorly prepared for global climate change. I have analyzed the metabolic and cellular response of Trematomus bernacchii, Pagothenia borchgrevinki and Trematomus newnesi to a long-term, multi-stressor scenario relevant to the predicted changes in the Southern Ocean. By combining whole animal respirometry with cellular level analysis of energy allocation, osmoregulatory mechanisms and cellular …

Ferric Reductases And Transporters That Contribute To Mitochondrial Iron Homeostasis, Anshika Jain

Theses and Dissertations

Iron (Fe) is the fourth most abundant element in the Earth’s crust, yet the availability of Fe to plants is often limited. This is because in most soil types, Fe precipitates as ferric-oxyhydroxy complexes, making it unavailable for uptake by plants. While the mechanisms involved in Fe uptake from the soil are relatively well understood, the mechanisms involved in its further distribution to the aerial portion of the plant and to subcellular compartments are not fully understood. During Fe deprivation, plants up-regulate root Fe acquisition machinery. How plants sense Fe deprivation and tie the Fe status of the plant to …

Molecular Mechanisms Of Gap Junction Regulation By The E3 Ubiquitin Ligase Wwp1, Measho Hagos Abreha

Theses and Dissertations

Ubiquitylation is a post-translational modification that influences a wide variety of cellular processes including protein degradation, protein subcellular localization, cell cycle progression, transcription, and DNA damage repair. Covalent attachment of the small ubiquitin molecule to a target protein involves the sequential action of three enzymes (E1, E2, and E3). In this process, substrate specificity is conferred by the E3 ligase. Our work has focused on the function of one such E3 ubiquitin ligase, WWP1. Known targets of WWP1 include cell cycle proteins, tumor suppressors, and transcription factors that promote differentiation of mesenchymal stem cells to the osteoid lineage. Recently, we …

Diversity, Genetics, And Health Benefits Of Sorghum Grain, Davina Rhodes

Theses and Dissertations

Staple cereal crops provide the majority of nutrients to the world's population, and thus, can significantly impact human nutrition and health. Phenotypic and genetic diversity within a crop can be useful for biofortification and crop improvement, but quantitative phenotyping is needed to identify varieties with high or low concentrations of a nutrient of interest, and to identify alleles responsible for quantitative trait variation of the nutrient. Sorghum [Sorghum bicolor (L.) Moench] is a diverse and widely adapted cereal crop that provides food for more than 500 million people in sub-Saharan Africa and Asia, and is becoming increasingly popular in specialty …

Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco

Theses and Dissertations

Untangling natural systems’ complexity requires understanding the mechanisms responsible for organisms’ responses to environmental change. Recently, significant advances have been made by recognizing the relevance of direct and indirect effects, which take place when multiple biotic and abiotic factors influence each other. I examined potential direct effects of environmental variables on a predator-prey interaction, as well as potential indirect effects of these variables on the interaction itself. I placed emphasis on behavioral and physiological adaptations, which would potentially contribute/modify these effects. My study system was comprised of a rocky intertidal keystone predator, the sea star Pisaster ochraceus, and its main …

Compositional Traits In Sorghum Bicolor Characterized By Transcriptome, Ionome And Genome-Wide Association Analysis, Nadia Shakoor

Theses and Dissertations

To address the challenge of global mineral malnutrition, current biofortification research in crop plants aims to improve mineral concentration and micronutrient bioavailablity via genetic and traditional breeding methods. Many staple food crops are also used as biofuels, and the chemical and mineral composition of these energy crops directly affect biomass quality and subsequent energy output. Identification of genes and QTL that impact mineral and compositional traits in the grain and biomass of major cereals, including sorghum, is fundamental to developing breeding and selection methods aimed at increasing bioavailable minerals and improving biofuel suitability and seed nutritional quality. A combinatorial strategy …

An Essential Role For Self-Pmhc Throughout The Life Of A Cd4 T Cell: Contributions In The Thymus And Periphery, Stephanie Rodriguez

Arts & Sciences Electronic Theses and Dissertations

It is well established that self-peptide Major Histocompatibility Complexes (hereafter self-pMHC) are essential for the development of a broad repertoire of mature, self-tolerant CD4 and CD8 T cells. Despite clear knowledge that the pool of self-ligands is critical for positive and negative selection, the exact kinetics and dynamic nature of thymocyte interaction with self-pMHC class II (self-pMHCII) bearing antigen-presenting cells (APCs) during development is still largely a mystery. The enigmatic nature of selecting self-pMHC is not unique to the thymic environment; increasingly evident is the dependence of peripheral T cells on extra-thymic self-pMHC expression, specifically selecting self-pMHC, for their homeostatic …

Evolution Of Ecological Dominance Of Yeast Species In High-Sugar Environments, Kathryn Marie Williams

Arts & Sciences Electronic Theses and Dissertations

Two challenging goals of evolutionary biology are to understand how evolutionary innovations evolve and how they contribute to the success of lineages. Evolutionary innovations may arise following whole genome duplication (WGD) events and they are suspected to contribute to the success of lineages by creating ecological opportunity. However, direct evidence for duplicated genes involved in evolutionary innovations remains rare, and the relationship between evolutionary innovations and the success of lineages may be very complex. In this study, I explore the relationship of evolutionary innovation, WGD, and the ecological dominance of yeast species in high-sugar environments. In budding yeast, a major …

Origin Of Maternal Age Effect In Congenital Heart Disease Risk For Offspring, Claire Elaine Schulkey

Arts & Sciences Electronic Theses and Dissertations

Increasing maternal age is widely acknowledged to lead to greater likelihood of pregnancy complications and congenital abnormalities, but the basis of this effect has not been well studied. Often dismissed as the product of oocyte ageing, the mechanistic basis of this maternal age effect is likely more complex.

Congenital heart disease is a classic complex disease with multiple genetic and environmental modifiers, including maternal age. Maternal ageing is a known risk-factor in humans, and has been shown to exist in an Nkx2-5 haploinsufficient mouse model for the disease. This mouse model's maternal age risk is dependent upon strain background, with …

Characterizing The Fitness Landscapes Of Gut Symbionts In Defined Community And Diet Contexts, Meng Wu

Arts & Sciences Electronic Theses and Dissertations

A species' niche is the description of all the environmental conditions required to permit a population of that species to persist, including the effects of the population on those conditions. This definition includes the species' resource requirements, as well as stress tolerances and interactions with other species acting as competitors, predators, parasites, and mutualists. The human gut microbiota serves as a microbial `metabolic organ' tasked in part with the biotransformation of many components of our diet. Relatively little is known about the factors that allow members of the human gut microbiota to persist in a habitat that experiences marked changes …