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It's A Small World: Biogeography And Invasion In The Mouse Intestine, Ellen Lark Jan 2015

It's A Small World: Biogeography And Invasion In The Mouse Intestine, Ellen Lark

Graduate Student Theses, Dissertations, & Professional Papers

Host associated systems are of particular interest to many microbiologists because invasion of these systems can lead to disease. One important host-associated systems is the intestinal microbiome, but in many studies, including those on pathogenesis, this system is represented by samples from one location (generally the feces or cecum). This body of work was initiated in part because I wondered why a large and diverse ecosystem was being was being represented by samples from only one habitat.

The biogeography of living organisms has an impact on landscape ecology studies, including those in the field of invasion ecology. Despite several studies …


Changes In Carbon Pools Influenced By Changes In Soil Texture, Slope, And Aspect A Decade Following Wildfire In Black Spruce Forests Of Interior Alaska, Gregory Houle Jan 2015

Changes In Carbon Pools Influenced By Changes In Soil Texture, Slope, And Aspect A Decade Following Wildfire In Black Spruce Forests Of Interior Alaska, Gregory Houle

Dissertations, Master's Theses and Master's Reports

Topography and parent material (PM) texture control site drainage owing to changes in water holding capacity, infiltration, and insolation. In turn, these factors also affect fire regime. However, the interactive effects of site physiography, edaphic controls, and wildfire severity on ecosystem carbon accrual after wildfire are poorly understood. Throughout the summer of 2004 an area the size of Massachusetts burned in interior Alaska, and several studies were initiated to investigate the controls on organic layer consumption. In this study we re-sampled organic layer depths, below ground carbon stocks, and site revegetation from 38 burned black spruce sites from the 2004 …


Parental Conversation Styles And Learning Science With Preschoolers, Emily A. Stone Jan 2015

Parental Conversation Styles And Learning Science With Preschoolers, Emily A. Stone

Honors Theses and Capstones

Preschool children participated in a science-learning event about light in their own classroom. The same day as the event, parents or caregivers were instructed to converse with their children at home in the evening about either the science learning event or another ‘special or fun’ event that happened to them recently in whatever way was natural for them. One week later, a researcher interviewed children to examine what they remembered about the science-learning event. Analyses focused on the impact of the topic and degree of elaboration of parent-child conversations on children’s memory for the science-learning event a week later. The …


The Effects Of Income Inequality On Society, Jessica Lee Clark Jan 2015

The Effects Of Income Inequality On Society, Jessica Lee Clark

Theses and Dissertations

This study is an examination of the relationship between income inequality and numerous indicators that capture the physical health of the citizens, additionally controlling for numerous other confounding factors. The analysis contributes to the literature by examining this relationship at a more disaggregated level within the Unites States than previous studies. This approach may help us to explore any impacts of income inequality on health that are lost in aggregation. The analysis also includes the most recent recession and adds to the literature the impact of inequality on health during a period of economic crisis. Results suggest that there is …


Ixodes Scapularis In North Dakota: Phenology, Population Genetics, And Local Host Reservoir Competency In An Emerging Vector Population, Michael Dougherty Jan 2015

Ixodes Scapularis In North Dakota: Phenology, Population Genetics, And Local Host Reservoir Competency In An Emerging Vector Population, Michael Dougherty

Theses and Dissertations

Tick surveillance in eastern North Dakota has revealed the presence of established I. scapularis populations in fragmented forest habitats previously regarded as unsuitable for this species. Understanding I. scapularis phenology, the reservoir competency of local vertebrate hosts, and population structure of blacklegged ticks in this region is essential to determining potential human risk of Lyme disease. Tick surveys were conducted throughout North Dakota by flagging and small mammal trapping. 1,701 ticks were collected, including 297 I. scapularis exhibiting a relatively low Borrelia burgdorferi infection rate (ca. 3-5%). Seasonal abundance varied greatly among life stages, with adult I. scapularis being most …


Parasites Within Parasites: Transmission And Evolution Of Neorickettsia In Digeneans, Stephen Edward Greiman Jan 2015

Parasites Within Parasites: Transmission And Evolution Of Neorickettsia In Digeneans, Stephen Edward Greiman

Theses and Dissertations

Digeneans are endoparasitic flatworms with complex life cycles that involve two or more different animals as definitive and intermediate hosts. Some digenean species harbor bacterial endosymbionts belonging to the genus Neorickettsia (Order: Rickettsiales, Family: Anaplasmataceae). Neorickettsia occur in all life cycle stages of digeneans and are maintained by vertical transmission. Far from benign however, Neorickettsia may also be transmitted horizontally by digenean parasites to their vertebrate definitive hosts. Once inside, Neorickettsia can infect macrophages and other cell types. For some vertebrate species (e.g. dogs, horses and humans), neorickettsial infections cause severe disease. With a few exceptions, studies of Neorickettsia have …


Linking Photosynthesis Physiology Of Upland Hardwood Reproduction To Ecology And Silviculture In The Arkansas Ozarks, Kutcher K. Cunningham Dec 2014

Linking Photosynthesis Physiology Of Upland Hardwood Reproduction To Ecology And Silviculture In The Arkansas Ozarks, Kutcher K. Cunningham

Theses and Dissertations

Oak (Quercus) forests in the Arkansas Ozarks have been important culturally, ecologically and environmentally for centuries. Historically these forests were fire dependent and dominated by oak species. In the past century, fire suppression and land management have caused these forests to densify. As a result, oaks are increasingly less abundant following disturbance in natural hardwood stands. Many applied ecological studies have explored methods and practices to maintain oak species in newly developing stands. This study attempted to link the mechanistic physiology of oak and non-oak reproduction to the applied ecological work. Varying stand conditions were generated in an undisturbed mature …


The History And Development Of De-Swiddening Among The Ersu In Sichuan, China, Edwin A. Schmitt Dec 2014

The History And Development Of De-Swiddening Among The Ersu In Sichuan, China, Edwin A. Schmitt

HIMALAYA, the Journal of the Association for Nepal and Himalayan Studies

The process of coercing or forcing farmers to transition from shifting agriculture to more sedentary agricultural practices, a process I refer to as “de-swiddening”, has been well documented for many decades. Most often this process takes place in the political context of a state’s attempt to make an agricultural system more “legible”, as Scott (1998) has aptly described it. In a more recent context, de-swiddening has actually been taken under the banner of environmental protection. In both instances, institutional bodies which design de-swiddening policies rarely consider its unintended consequences. In China, to prevent erosion in upland regions of the country, …


Feeding Ecology And Movement Patterns Of Juvenile Sablefish In Coastal Southeast Alaska, Karson Marie Coutré Dec 2014

Feeding Ecology And Movement Patterns Of Juvenile Sablefish In Coastal Southeast Alaska, Karson Marie Coutré

Fisheries

Sablefish, Anoplopoma fimbria, is a commercially valuable groundfish species undergoing population declines in the Gulf of Alaska and Bering Sea. This study assessed the role of juvenile sablefish as consumers in coastal Southeast Alaska (St. John Baptist Bay, Baranof Island, Alaska; SJBB) to better understand their use of habitat and food resources during their early life history. Specifically, the diet of juvenile sablefish was described for multiple seasons (summer and fall) and years (2012 and 2013) from analysis of stomach contents recovered using gastric lavage. Sablefish ate a wide variety of prey taxa, and the most important prey groups were …


Biotic And Abiotic Influences On The Use Of Arctic Lakes By Fish And Loons, Trevor B. Haynes Dec 2014

Biotic And Abiotic Influences On The Use Of Arctic Lakes By Fish And Loons, Trevor B. Haynes

Fisheries

The particularly severe effects of climate change anticipated in the Arctic, accompanied by ongoing anthropogenic activities, necessitate proactive and knowledge-based management of the region's aquatic ecosystems. However, the paucity of information on the Arctic's aquatic environments hinders strategic or spatially-explicit management. In this dissertation, I examine the habitat use of poorly studied taxa of the Arctic Coastal Plain (ACP) of Alaska, including freshwater fishes and yellow-billed loons (Gavia adamsii). Distribution studies can be biased by false absences; therefore, I began by determining the detection probabilities of six fish species common to Arctic lakes for five gear types (Chapter 2). Variation …


Annual Report: 2013, N/A N/A Dec 2014

Annual Report: 2013, N/A N/A

Annual Reports

I submit herewith the annual reports from the Agricultural and Forestry Experiment Station, School of Natural Resources and Agricultural Sciences, University of Alaska Fairbanks, for the period ending December 31, 2013. This is done in accordance with an act of Congress, approved March 2, 1887, entitled, “An act to establish agricultural experiment stations, in connection with the agricultural college established in the several states under the provisions of an act approved July 2, 1862, and under the acts supplementary thereto,” and also of the act of the Alaska Territorial Legislature, approved March 12, 1935, accepting the provisions of the act …


Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson Dec 2014

Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson

Theses and Dissertations

Climate change is having demonstrable, worldwide impacts on ecological systems in ways that have modified aspects of organism behavior. Plant phenologies have responded to warmer temperatures in a variety of ways that may have implications for long-term species survival. How germination phenology changes in response to warmer climate is a largely unexplored question yet the ability of a plant to advance or delay germination in unfavorable conditions is critical for survival. Knowing the relative success and timing of germination under different climate regimes is important in understanding whether species can keep pace with the rate of climate change via migration …


Effect Of Primary Care Physician Density On Late Stage Cervical Cancer Diagnosis, Emily Haanschoten Dec 2014

Effect Of Primary Care Physician Density On Late Stage Cervical Cancer Diagnosis, Emily Haanschoten

Theses and Dissertations

INTRODUCTION: Late-stage cervical cancer diagnosis is an important contributing factor to the cervical cancer mortality rate. Screening for cervical cancer is a vital tool in reducing the number of late-stage cases, preventing incident cases and reducing mortality. Access to care is often a significant barrier to receiving these services. Women who have no usual source of care report significantly lower percentages of Pap tests than women who have a usual source. South Carolina ranks 13th in the US in cervical cancer incidence and 7th in cervical cancer mortality. South Carolina also struggles with a primary care physician shortage, ranking 39th …


Spatial Dynamics Of Vegetated Seascapes And The Influence On Fish And Crustaceans, Rolando O. Santos Corujo Dec 2014

Spatial Dynamics Of Vegetated Seascapes And The Influence On Fish And Crustaceans, Rolando O. Santos Corujo

Open Access Dissertations

My dissertation adopted concepts and spatial tools of seascape ecology, the marine counterpart of landscape ecology, to understand the broad-scale structural attributes that make submerged aquatic vegetation (SAV) seascapes resilient to anthropogenic disturbances, drivers of fauna community structure, and productive fisheries habitats. My research was designed to address the relative and interrelated ecological effects of broad-scale changes in SAV habitat amount (habitat loss) and configuration (fragmentation). SAV seascapes in nearshore areas of Biscayne Bay have been subject to constant anthropogenic disturbances associated to freshwater pulses from canals over the last 50 years; thus, these seascapes served as a model system …


Soil Respiration Patterns And Controls In Limestone Cedar Glades, Jennifer Cartwright, Dafeng Hui Dec 2014

Soil Respiration Patterns And Controls In Limestone Cedar Glades, Jennifer Cartwright, Dafeng Hui

Biology Faculty Research

Aims

Drivers of soil respiration (R s ) in rock outcrop ecosystems remain poorly understood. We investigated these drivers in limestone cedar glades, known for their concentrations of endemic plant species and for seasonal hydrologic extremes (xeric and saturated conditions), and compared our findings to those in temperate grasslands and semi-arid ecosystems.

Methods

We measured R s , soil temperature (T s ), volumetric soil water content (SWC), soil organic matter (SOM), soil depth, and vegetation cover monthly over 16 mo and analyzed effects of these variables on R s .

Results

Seasonally, R s primarily tracked T …


Avian Diversity Across Three Distinct Agricultural Landscapes In Guadalupe, Chiriquí Highlands, Panama, Jarred Jones Dec 2014

Avian Diversity Across Three Distinct Agricultural Landscapes In Guadalupe, Chiriquí Highlands, Panama, Jarred Jones

Independent Study Project (ISP) Collection

Deforestation of tropical forest for agricultural purposes threatens habitat loss of native species. The value of various agricultural landscapes in conserving avian populations is useful in determining diversity-conscious development plans. However, generalized results from regionalscale studies cannot be implemented to insular avian habitats. This study serves as the only current avian diversity study of the Chiriquí Highlands. To determine the effect of agricultural land use within an insular avian habitat, I compared avian diversity and site population similarity in Guadalupe, Chiriquí Highlands of the Talamanca Range, Panama. I hypothesized that avian diversity is greatest at forest edge followed by forest …


Genetic And Environmental Variation In Condition, Cutaneous Immunity, And Haematocrit In House Wrens, Scott K. Sakaluk, Laura A. Vogel, Alastair J. Wilson, E. Keith Bowers, L. Scott Johnson, Brian S. Masters, Bonnie Gp Johnson, Anna M. Forsman, Charles F. Thompson Dec 2014

Genetic And Environmental Variation In Condition, Cutaneous Immunity, And Haematocrit In House Wrens, Scott K. Sakaluk, Laura A. Vogel, Alastair J. Wilson, E. Keith Bowers, L. Scott Johnson, Brian S. Masters, Bonnie Gp Johnson, Anna M. Forsman, Charles F. Thompson

Faculty Publications – Biological Sciences

Background

Life-history studies of wild bird populations often focus on the relationship between an individual’s condition and its capacity to mount an immune response, as measured by a commonly-employed assay of cutaneous immunity, the PHA skin test. In addition, haematocrit, the packed cell volume in relation to total blood volume, is often measured as an indicator of physiological performance. A multi-year study of a wild population of house wrens has recently revealed that those exhibiting the highest condition and strongest PHA responses as nestlings are most likely to be recruited to the breeding population and to breed through two years …


The Unseen World: Environmental Microbial Sequencing And Identification Methods For Ecologists, Naupaka Zimmerman, Jacques Izard, Christian Klatt, Jizhong Zhou, Emma Aronson Dec 2014

The Unseen World: Environmental Microbial Sequencing And Identification Methods For Ecologists, Naupaka Zimmerman, Jacques Izard, Christian Klatt, Jizhong Zhou, Emma Aronson

Department of Food Science and Technology: Faculty Publications

Archaea, bacteria, microeukaryotes, and the viruses that infect them (collectively “microorganisms”) are foundational components of all ecosystems, inhabiting almost every imaginable environment and comprising the majority of the planet’s organismal and evolutionary diversity. Microorganisms play integral roles in ecosystem functioning; are important in the biogeochemical cycling of carbon (C), nitrogen (N), sulfur (S), phosphorus (P), and various metals (eg Barnard et al. 2005); and may be vital to ecosystem responses to large-scale climatic change. Rarely found alone, microorganisms often form complex communities that are dynamic in space and time. For these and other reasons, ecologists and environmental scientists have become …


The Influence Of Salt Marsh Fucoid Algae (Ecads) On Sediment Dynamics Of Northwest Atlantic Marshes, M. C. Tyrrell, Carol S. Thornber, J. A. Burkhardt, M. Congretel Dec 2014

The Influence Of Salt Marsh Fucoid Algae (Ecads) On Sediment Dynamics Of Northwest Atlantic Marshes, M. C. Tyrrell, Carol S. Thornber, J. A. Burkhardt, M. Congretel

Biological Sciences Faculty Publications

Resilience is currently a key theme within salt marsh ecological studies. Understanding the factors that affect salt marsh accretion and elevation gains are of paramount importance if management of these ecosystems is to be successful under increasing synergistic stresses of storm surge, inundation period, and eutrophication. We present the results of salt marsh fucoid algae (ecads) removal experiments on Spartina alterniflora abundance, production and decomposition and the sedimentary dynamics of two marshes on Cape Cod, Massachusetts. The presence of the thick layer of marsh fucoids had a significant and positive influence on sediment deposition, accretion, concentration of water column particulates, …


Trophic Dynamic Interactions In A Temperate Karst River, Elizabeth Malloy Dec 2014

Trophic Dynamic Interactions In A Temperate Karst River, Elizabeth Malloy

Masters Theses & Specialist Projects

Surface streams in karst landscapes are often characterized by high nutrient levels due to incomplete filtration through series of innumerable, below-ground conduits. Seasonal growth of the filamentous alga, Cladophora, is typically associated with nutrient-rich waters. This research compared macroinvertebrate food web structure between riverine reaches with contrasting underlying karst topography, nutrient levels, and Cladophora cover during summer 2012 and autumn 2013. Recent work in these reaches found a high correlation between Cladophora cover and nutrient content, particularly nitrate. Four questions were addressed during this study: 1. Do longitudinal trends in algal and consumer δ13C values relate to decreased DIC availability …


The Potential Of Exogenous Fatty Acids In Breast Tissue Engineering, Richard Thomas Pace Dec 2014

The Potential Of Exogenous Fatty Acids In Breast Tissue Engineering, Richard Thomas Pace

All Dissertations

More than 200,000 women are diagnosed with breast cancer each year in the United States, where the majority will undergo a lumpectomy procedure and then radiotherapy as preventative treatment. Both artificial and tissue transplants may obscure the detection of cancer recurrence or limit the effectiveness of radiation treatment. Previous research in our laboratory has been performed to develop injectable lumpectomy void fillers. This body of work seeks to continue and further develop the technology of the void fillers and further investigate the potential of fatty acids in breast tissue engineering.

Literature suggests that lipid peroxidation products from free fatty acids …


The Vascular Flora Of Steele Creek Park And A Quantitative Study Of Vegetation Patterns In Canopy Gaps, Sullivan County, Tennessee, Phillip C. Klahs Dec 2014

The Vascular Flora Of Steele Creek Park And A Quantitative Study Of Vegetation Patterns In Canopy Gaps, Sullivan County, Tennessee, Phillip C. Klahs

Electronic Theses and Dissertations

An inventory of vascular plants was conducted in Steele Creek Park in Sullivan County, Tennessee from March 2013 to September 2014. The park covers an area of 892 ha and lies within the Ridge and Valley Province. The inventory of vascular plants documented 547 species of 323 genera and 101 families. Two hundred sixteen taxa were newly reported for Sullivan County. Tennessee Special Concern Species included Cardamine rotundifolia, Castanea dentata, Lonicera dioica, Allium tricoccum, Cypripedium acaule, and Panax quinquefolius. A single species, Juglans cinerea L., is considered a Tennessee Threatened Species. Vegetation patterns were studied quantitatively by installing 10 …


Benthic Macroinvertebrates In Uvas Creek, California, Downstream Of A Reservoir, Carole Ann Foster Dec 2014

Benthic Macroinvertebrates In Uvas Creek, California, Downstream Of A Reservoir, Carole Ann Foster

Master's Theses

I sampled macroinvertebrates in May, July, and October 2008 in Uvas Creek, a reservoir-regulated stream in south Santa Clara County, California, to assess what factors (including canopy closure, turbidity, and stream flow) downstream of the reservoir were related to food availability for rearing juvenile Steelhead (Oncorhynchus mykiss). I found benthic and drifting macroinvertebrate biomass was considerably greater during most months in the more open-canopied two sites in the downstream reach as compared to the densely shaded, more turbid and silty two sites in the upstream reach. Abundance of important drifting aquatic invertebrates in May (chironomids, simuliids, and baetids) was proportional …


Keeping In Touch: Exchange As An Adaptive Strategy In Southern Nevada, Timothy Joshua Ferguson Dec 2014

Keeping In Touch: Exchange As An Adaptive Strategy In Southern Nevada, Timothy Joshua Ferguson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Archaeologists have always wondered about the extent of vessel movement in the American Southwest. Identifying vessel movement allows for the study of social interactions across a region and the role of ceramics in the adaptive processes of agriculturalists living in marginal, highly variable environments. In many instances, exchange may act as a way to reduce the risk of resource shortfalls by creating social ties in other areas. This research investigated the changing risk reduction strategies of households in the lowland Virgin region of southern Nevada by using geochemical methods to trace the exchange of locally produced pottery. It was hypothesized …


Geographic Assessment Of The Perception Of Nature Reserves And National Parks In Kuwait, Meshari S. Alenezi Dec 2014

Geographic Assessment Of The Perception Of Nature Reserves And National Parks In Kuwait, Meshari S. Alenezi

Graduate Theses and Dissertations

The Arabian Gulf countries have passed strict laws to preserve their environment. Kuwait has a strong history with preserving natural areas. The ecological value and richness of Kuwait's ecosystems have increased since the nature reserves were built. This research has evaluated the perceptions that Kuwaitis have of the design, creation, and development of nature reserves in Kuwait. It involved the use of survey instruments (questionnaires) and interviews with respondents of both urban and rural communities. Data from these surveys and interviews analyzed regarding perceptions of nature reserves' needs, sizes, functions, and future plans.

The results of examinations (surveys) demonstrate that …


A Review Of Software For Analyzing Molecular Sequences, Haema Nilakanta, Kimberly L. Drews, Suzanne Firrell, Mary A. Foulkes, Kathleen A. Jablonski Nov 2014

A Review Of Software For Analyzing Molecular Sequences, Haema Nilakanta, Kimberly L. Drews, Suzanne Firrell, Mary A. Foulkes, Kathleen A. Jablonski

GW Biostatistics Center

Background Over the past ten years, there has been an explosion of microbiome research. Many software packages for analyzing microbial sequences such as the 16S gene from 454 sequencers and Illumina platforms are available. But for a new researcher, it is difficult to know which package to choose. We present a systematic review of packages for the analysis of molecular sequences used to describe and compare microbial communities. This review gives students and researchers information to help choose the best analytic pipeline for their project. To the best of our knowledge, this is the first review of such software.

Findings …


Local Modelling Techniques For Assessing Micro-Level Impacts Of Risk Factors In Complex Data: Understanding Health And Socioeconomic Inequalities In Childhood Educational Attainments, Shang Ming Zhou, Ronan A. Lyons, Owen G. Bodger, Ann John, Huw Brunt, Kerina Jones, Mike B. Gravenor, Sinead Brophy Nov 2014

Local Modelling Techniques For Assessing Micro-Level Impacts Of Risk Factors In Complex Data: Understanding Health And Socioeconomic Inequalities In Childhood Educational Attainments, Shang Ming Zhou, Ronan A. Lyons, Owen G. Bodger, Ann John, Huw Brunt, Kerina Jones, Mike B. Gravenor, Sinead Brophy

School of Nursing and Midwifery

No abstract provided.


Short- And Long-Term Trends In Ecological Interactions: From Predator-Prey Interactions To Phanerozoic Diversification, Subhronil Mondal Nov 2014

Short- And Long-Term Trends In Ecological Interactions: From Predator-Prey Interactions To Phanerozoic Diversification, Subhronil Mondal

USF Tampa Graduate Theses and Dissertations

During the last two decades, a broad spectrum of short- and long-term studies on different taxonomic groups has enriched our understanding about how dynamics of taxonomic and ecological diversification have changed through geologic time. There are two major issues that have impacted these studies: the quality and quantity of data used are often insufficient in various ways and the methods used may produce results that are more equivocal than supposed. To investigate these issues more fully, this dissertation focuses on studies on two major aspects: 1) short-term studies examining the nature of successful and unsuccessful predatory attacks on Plio-Pleistocene bivalves; …


Statistical Analysis And Modeling Of Pm2.5 Speciation Metals And Their Mixtures, Boubakari Ibrahimou Nov 2014

Statistical Analysis And Modeling Of Pm2.5 Speciation Metals And Their Mixtures, Boubakari Ibrahimou

USF Tampa Graduate Theses and Dissertations

Exposure to fine particulate matter (PM2.5) in the ambient air is associated with various health effects. There is increasing evidence which implicates the central role played by specific chemical components such as heavy metals of PM2.5. Given the fact that humans are exposed to complex mixtures of environmental pollutants such as PM2.5, research efforts are intensifying to study the mixtures composition and the emission sources of ambient PM, and the exposure-related health effects. Factor analysis as well source apportionment models are statistical tools potentially useful for characterizing mixtures in PM2.5. However, classic …


Cosm News, Georgia Southern University Nov 2014

Cosm News, Georgia Southern University

College of Science & Mathematics: News & Publications (2012-2022)

  • Georgia Southern professor and graduate student replicate the tide
  • Scientists replicate the tide with two buckets, aquarium tubing, and a pump