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Recreation Ecology Of Colorado Fourteeners: An Assessment Of Trail Usage And Impacts, James C. Ewing Dec 2015

Recreation Ecology Of Colorado Fourteeners: An Assessment Of Trail Usage And Impacts, James C. Ewing

Master's Theses

The popularity of climbing Colorado’s 14,000 ft. peaks, or “Fourteeners”, has risen dramatically in recent years, raising important sustainability and management questions. Moreover, groups managing the peaks operate with major capital constraints so their efforts need to be informed, prioritized, and efficient. This paper gauges the dynamics of trail usage, explanatory variables, and recreational impacts across all 58 Fourteeners, and details evaluation adjustments that minimize error and produce results in-step with the resource management framework. Relative to a baseline study completed in 2005, substantial changes occurred in trail usage and impact dynamics. The greatest changes were concentrated on peaks previously …


In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers Nov 2015

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

USF Tampa Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit …


Increased Taxonomic And Functional Similarity Does Not Increase The Trophic Similarity Of Communities, Thomas K. Pool, Julien Cucherousset, Stéphanie Boulêtreau, Sébastien Villéger, Angela L. Strecker, Gaël Grenouillet Nov 2015

Increased Taxonomic And Functional Similarity Does Not Increase The Trophic Similarity Of Communities, Thomas K. Pool, Julien Cucherousset, Stéphanie Boulêtreau, Sébastien Villéger, Angela L. Strecker, Gaël Grenouillet

Environmental Science and Management Faculty Publications and Presentations

Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship remains limited. Community assembly theory predicts that niche partitioning will result in communities with a diverse array of functional traits, which in turn may facilitate a correspondingly diverse array of trophic interactions that define the trophic niche of those communities. The aim of our study is to test this prediction.

Methods: We built a database composed of functional traits and stable isotope values (δ13C and δ15N) for …


'At-Risk' Places: Inequaties In The Distribution Of Environmental Stressors And Prescription Rates Of Mental Health Medications In Glasgow, Scotland, Juliana A. Maantay, Andrew Maroko Oct 2015

'At-Risk' Places: Inequaties In The Distribution Of Environmental Stressors And Prescription Rates Of Mental Health Medications In Glasgow, Scotland, Juliana A. Maantay, Andrew Maroko

Publications and Research

Using geospatial analytical methods, this study examines the association between one aspect of the built environment, namely, the concentration of vacant and derelict land (VDL), and the prevalence of mental health disorders (using the proxy variable of mental health medication prescription rates) in Glasgow, Scotland. This study builds on our previous research, which demonstrated the spatial correspondence between the locations of VDL in Glasgow and several physical health outcomes. Numerous studies of other locales have found similar correspondence between different elements of the built environment and various health outcomes. This is the first study of its kind to look at …


Biodiversity And Ecological Dynamics Of Sciophilous Benthic Communities On Artificial Plates: Emphasis On Reef Sponges, Caidra Elizabeth Hassanzada Oct 2015

Biodiversity And Ecological Dynamics Of Sciophilous Benthic Communities On Artificial Plates: Emphasis On Reef Sponges, Caidra Elizabeth Hassanzada

HCNSO Student Theses and Dissertations

Low light intensity habitats harbor unique sciophilous benthic communities and are a source of novel and unique sponge fauna. However, the community structure of these habitats is poorly studied to date. Thus, this study attempts to understand the composition and structure of sciophilous sponge populations in southeast Florida. Fifty limestone plates were placed on a shallow reef in Fort Lauderdale for two years (2010-2012). To identify the sponge community and their patterns over time, all plates were photographed at the end of each year. Then, samples were taken from each of the live sponge specimens observed on the plates and …


Supporting Teachers’ Learning About Mathematical Modeling, June L. Gastón, Barbara A. Lawrence Oct 2015

Supporting Teachers’ Learning About Mathematical Modeling, June L. Gastón, Barbara A. Lawrence

Publications and Research

In the United States, one of the Standards for Mathematical Practice of the Common Core Curriculum (Common Core State Standards Initiative, 2010) is Model with mathematics. This standard requires that students be taught in a manner that will enable them to ―apply the mathematics they know to solve problems arising in everyday life, society, and the workplace‖ (p. 7). However many prospective and practicing teachers acquire a pedagogical style that does not support this standard. To promote higher levels of student thinking associated with mathematical modeling, teachers must thus be taught not only what mathematical modeling is, but how it …


Guide To The Dr. Jane Claire Dirks-Edmunds Papers, Linfield College Archives Oct 2015

Guide To The Dr. Jane Claire Dirks-Edmunds Papers, Linfield College Archives

Linfield Archives Finding Aids

This collection reflects the life work of Dr. Jane Claire Dirks-Edmunds, a student and professor of Linfield College. A dedicated and scrupulous woman, the majority of the collection consists of her research, teaching materials, and correspondence. The collection also includes research and correspondence by Dr. Jane Claire Dirks-Edmunds’s mentor, Dr. James A. Macnab.


Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain Oct 2015

Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain

Virginia Journal of Science

The Virginia landscape supports a remarkable diversity of forests, from maritime dune woodlands, swamp forests, and pine savannas of the Atlantic Coastal Plain, to post-agricultural pine-hardwood forests of the Piedmont, to mixed oak, mesophytic, northern hardwood, and high elevation spruce-fir forests across three mountain provinces in western parts of the state. Virginia’s forests also have been profoundly shaped by disturbance. Chestnut blight, hemlock woolly adelgid, emerald ash borer, and other pests have caused declines or functional extirpation of foundation species. Invasive plants like multiflora rose, Oriental bittersweet, and Japanese stiltgrass threaten both disturbed and intact forests. Oaks and other fire-dependent …


Feasibility And Informative Value Of Environmental Sample Collection In The National Children's Vanguard Study, Elizabeth Barksdale Boyle, Nicole C. Deziel, Bonny L. Specker, Scott Collingwood, Clifford P. Weisel, David J. Wright, Michael Dellarco Jul 2015

Feasibility And Informative Value Of Environmental Sample Collection In The National Children's Vanguard Study, Elizabeth Barksdale Boyle, Nicole C. Deziel, Bonny L. Specker, Scott Collingwood, Clifford P. Weisel, David J. Wright, Michael Dellarco

Ethel Austin Martin Program Publications

Background: Birth cohort studies provide the opportunity to advance understanding of the impact of environmental factors on childhood health and development through prospective collection of environmental samples. Methods: We evaluated the feasibility and informative value of the environmental sample collection methodology in the initial pilot phase of the National Children's Study, a planned U.S. environmental birth cohort study. Environmental samples were collected from January 2009–September 2010 at up to three home visits: pre-pregnancy (n¼306), pregnancy (n¼807), and 6-months postnatal (n¼117). Collections included air for particulate matter r2.5 mm (PM2.5), nitrogen dioxide, ozone, volatile organic compounds (VOCs), and carbonyls; vacuum dust …


Localized Ecological And Educational Effects Of Environmental Service-Learning In Portland, Oregon, Steven Matthew Braun Jun 2015

Localized Ecological And Educational Effects Of Environmental Service-Learning In Portland, Oregon, Steven Matthew Braun

Dissertations and Theses

Environmental service-learning is an intentional educational experience(s) wherein learners engage in meaningful activities designed to serve the environment. Environmental service-learning activities vary according to their learning and service goals and include ecomanagement, persuasion, legal action, economic action and political action. The purpose of this mixed methods research was to explore the ecological and educational impacts of grades 6-12 environmental education, with special attention to environmental service-learning throughout Portland, Oregon.

Ecological impacts considered restoration and conservation outcomes of several environmental service-learning programs including plant communities, soils, litter removal and trail maintenance. Educational outcomes considered aspects of environmental literacy including locus of …


Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg Jun 2015

Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg

Natural Resource Management Faculty Publications

Alloparental care (i.e., care for unrelated offspring) has been documented in various avian species (Maxson 1978, Smith et al. 1996, Tella et al. 1997, Lislevand et al. 2001, Literak and Mraz 2011). A male replacement mate that encounters existing broods has options, which include alloparental care or infanticide. Infanticide may be beneficial in some species (Rohwer 1986, Kermott et al. 1990), but in long-lived avian species, like the ferruginous hawk (Buteo regalis) that do not renest within a season, infanticide might be detrimental. Adoption and rearing success likely provide direct evidence of competence of replacement mates as potential parents for …


Ion Interactions At The Mineral-Water Interface During Biogeochemical Iron And Manganese Cycling, Margaret A. G. Hinkle May 2015

Ion Interactions At The Mineral-Water Interface During Biogeochemical Iron And Manganese Cycling, Margaret A. G. Hinkle

Arts & Sciences Graduate Student Theses and Dissertations

The biogeochemical cycling of iron and manganese involves the reductive dissolution and oxidative precipitation of Fe(III) and Mn(IV/III) oxides. Biogenic Fe(III) and Mn(IV/III) oxides are often characterized by high surface areas and therefore high sorptive capacities. As a result, these minerals can substantially alter the chemistry of natural waters and the availability of micronutrients in soils and sediments by scavenging trace metals. Recent research indicates that the adsorption of aqueous Fe(II) onto Fe(III) oxides involves oxidative adsorption, electron transfer, and subsequent reductive dissolution at another surface site [a process collectively referred to as `electron transfer-atom exchange' (ET-AE)]. Aqueous Mn(II) adsorption …


Hydrologic Mediation Of The Spatial And Temporal Variability Of The Soil Carbon Dioxide Stable Isotopic Composition Of A Subalpine Watershed, Theresa Marie Lorenzo May 2015

Hydrologic Mediation Of The Spatial And Temporal Variability Of The Soil Carbon Dioxide Stable Isotopic Composition Of A Subalpine Watershed, Theresa Marie Lorenzo

School of Natural Resources: Dissertations, Theses, and Student Research

The stable carbon isotopic composition of CO2 (δ13C-CO2) has been studied as an indicator of changes in ecosystem CO2 exchange. Soil moisture is an important factor in ecosystem CO2 exchange through its influence on physiological and soil physical processes. However, the majority of previous research analyzing the influence of soil moisture on soil and soil-respired δ13C-CO2 has been conducted with limited consideration of topographical variation, which controls the distribution of soil moisture across a landscape. This study characterized the stable isotopic composition (δ13C) and concentrations of soil CO …


Acute Toxicity Of Β-N-Methylamino-L-Alanine (Bmaa) To Fathead Minnow (Pimephales Promelas) And Zebrafish (Danio Rerio), Jiayi Wang May 2015

Acute Toxicity Of Β-N-Methylamino-L-Alanine (Bmaa) To Fathead Minnow (Pimephales Promelas) And Zebrafish (Danio Rerio), Jiayi Wang

School of Natural Resources: Dissertations, Theses, and Student Research

β-N-methylamino-L-alanine (BMAA) is a neurotoxic amino acid produced by most species of cyanobacteria. Exposure to BMAA has been hypothesized as a cause of ALS and possibly Parkinson’s and Alzheimer’s diseases for several decades. Both in vitro and in vivo experiments revealed that exposure to elevated concentrations of BMAA can damage motor neurons and cause motor dysfunctions. However, the exact mechanism of BMAA-induced neurotoxicity has not been well understood.

Based on the available literature and in spite of its water-soluble and non-protein nature, BMAA appears to be able to bioaccumulate in organisms. The ubiquity of cyanobacteria and the potential for bioaccumulation …


The Contribution Of Indigenous Ecological Knowledge In Conservation Of Enguserosambu Community Forest, Tanzania, Agnes Sirima May 2015

The Contribution Of Indigenous Ecological Knowledge In Conservation Of Enguserosambu Community Forest, Tanzania, Agnes Sirima

All Dissertations

Community managed forests constitute a significant proportion of the world's forests, however, little is known regarding their condition or the details of how they are managed. Documented benefits of community managed forest include poverty alleviation and in some places a decrease in the rate of deforestation. Although some community based forests do not satisfy the IUCN definition of a protected areas, they provide valuable long term sustainability of forest products and many are also rich in biodiversity and support landscape conservation strategies. Forests are also home to many cultures including the indigenous people. Indigenous communities surrounding forest areas and other …


Modeling Seed Dispersal And Population Migration Given A Distribution Of Seed Handling Times And Variable Dispersal Motility: Case Study For Pinyon And Juniper In Utah, Ram C. Neupane May 2015

Modeling Seed Dispersal And Population Migration Given A Distribution Of Seed Handling Times And Variable Dispersal Motility: Case Study For Pinyon And Juniper In Utah, Ram C. Neupane

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spread of fruiting tree species is strongly determined by the behavior and range of fruit-eating animals, particularly birds. Birds either consume and digest seeds or carry and cache them at some distance from the source tree. These carried and settled seeds provide some form of distribution which generates tree spread to the new location. Firstly, we modal seed dispersal by birds and introduce it in a dispersal model to estimate seed distribution. Using this distribution, we create a population model to estimate the speed at which juniper and pinyon forest boundaries move.

Secondly, we introduce a fact that bird …


Combining And Aggregating Environmental Data For Status And Trend Assessments: Challenges And Approaches, Kathleen G. Maas-Hebner, Michael Harte, Nancy Molina, Robert M. Hughes, Carl B. Schreck, J. Alan Yeakley May 2015

Combining And Aggregating Environmental Data For Status And Trend Assessments: Challenges And Approaches, Kathleen G. Maas-Hebner, Michael Harte, Nancy Molina, Robert M. Hughes, Carl B. Schreck, J. Alan Yeakley

Environmental Science and Management Faculty Publications and Presentations

Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess local-, regional-, and landscape-level environmental conditions, particularly status and trends, and to improve their ability to make short-and long-term management decisions. Status monitoring assesses the current condition of a population or environmental condition across an area. Monitoring for trends aims at monitoring changes in populations or environmental condition through time. We wrote this paper to inform agency and nongovernmental organization managers, analysts, and consultants regarding the kinds of environmental data that can be combined with suitable …


Investigation Of Bioactive Metabolites From The Antarctic Sponge Dendrilla Membranosa And Marine Microorganisms, Chris G. Witowski Apr 2015

Investigation Of Bioactive Metabolites From The Antarctic Sponge Dendrilla Membranosa And Marine Microorganisms, Chris G. Witowski

USF Tampa Graduate Theses and Dissertations

Natural products continue to be a valuable source of compounds in research involving chemical ecology and drug discovery. Secondary metabolites are biosynthesized to benefit the host organism in its environment (feeding deterrence from predators, antibiotic properties to avoid infection, etc.) but these compounds also serve as useful scaffolds in drug discovery applications. The research herein describes both aspects of these two branches of natural products chemistry. The Antarctic sponge Dendrilla membranosa produces diterpenes, of which membranolide A, deters feeding of the predatory amphipod Gondogenia antarctica. A metabolomic study of several sponges was undertaken to determine environmental factors that govern …


Development Modeling Of Lucilia Sericata (Diptera: Calliphoridae), Amanda Roe, Leon G. Higley Mar 2015

Development Modeling Of Lucilia Sericata (Diptera: Calliphoridae), Amanda Roe, Leon G. Higley

School of Natural Resources: Faculty Publications

The relationship between insect development and temperature has been well established and has a wide range of uses, including the use of blow flies for postmortem (PMI) interval estimations in death investigations. To use insects in estimating PMI, we must be able to determine the insect age at the time of discovery and backtrack to time of oviposition. Unfortunately, existing development models of forensically important insects are only linear approximations and do not take into account the curvilinear properties experienced at extreme temperatures. A series of experiments were conducted with Lucilia sericata, a forensically important blow fly species, that met …


Microbial Iron Mats At The Mid-Atlantic Ridge And Evidence That Zetaproteobacteria May Be Restricted To Iron-Oxidizing Marine Systems, Jarrod J. Scott, John A. Breier, George W. Luther Iii, David Emerson Mar 2015

Microbial Iron Mats At The Mid-Atlantic Ridge And Evidence That Zetaproteobacteria May Be Restricted To Iron-Oxidizing Marine Systems, Jarrod J. Scott, John A. Breier, George W. Luther Iii, David Emerson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Chemolithoautotrophic iron-oxidizing bacteria play an essential role in the global iron cycle. Thus far, the majority of marine iron-oxidizing bacteria have been identified as Zetaproteobacteria, a novel class within the phylum Proteobacteria. Marine iron-oxidizing microbial communities have been found associated with volcanically active seamounts, crustal spreading centers, and coastal waters. However, little is known about the presence and diversity of iron-oxidizing communities at hydrothermal systems along the slow crustal spreading center of the Mid-Atlantic Ridge. From October to November 2012, samples were collected from rust-colored mats at three well-known hydrothermal vent systems on the Mid-Atlantic Ridge (Rainbow, Trans-Atlantic Geotraverse, and …


Sulfidic Spring In The Gypsum Karst System Of Monte Conca (Italy): Chemistry And Microbiological Evidences, Marianna Messina, Tiziana Grech, Fiorenzo Fiorenza, Alessandro Marlettta, Pietro Valenti, Salvatore Petralia Feb 2015

Sulfidic Spring In The Gypsum Karst System Of Monte Conca (Italy): Chemistry And Microbiological Evidences, Marianna Messina, Tiziana Grech, Fiorenzo Fiorenza, Alessandro Marlettta, Pietro Valenti, Salvatore Petralia

International Journal of Speleology

Monte Conca Cave is a karst system placed in Messinian evaporites, consisting of an active cave and a resurgence located on the massif of Monte Conca, Campofranco within the "Riserva Naturale Integrale di Monte Conca". A sulfidic spring is located in the terminal gallery of the cave. To characterize the physical and chemical parameters of the Monte Conca cave and of the sulfidic spring, air temperature, relative humidity, water pH, and concentrations of dissolved sulfides, nitrates and sulfates were monitored. The high sulfide consumption rate in the sulfidic spring, evaluated by a kinetic study, suggests that biotic consumption is dominant. …


Cluster Of Human Infections With Avian Influenza A (H7n9) Cases: A Temporal And Spatial Analysis, Yi Zhang, Zhixiong Shen, Chunna Ma, Chengsheng Jiang, Cindy Feng, Nivedita Shankar, Peng Yang, Wenjie Sun, Quanyi Wang Jan 2015

Cluster Of Human Infections With Avian Influenza A (H7n9) Cases: A Temporal And Spatial Analysis, Yi Zhang, Zhixiong Shen, Chunna Ma, Chengsheng Jiang, Cindy Feng, Nivedita Shankar, Peng Yang, Wenjie Sun, Quanyi Wang

Marine Science

Objectives: This study aims to describe the spatial and temporal characteristics of human infections with H7N9 virus in China using data from February 2013 to March 2014 from the websites of every province’s Population and Family Planning Commission. Methods: A human infection with H7N9 virus dataset was summarized by county to analyze its spatial clustering, and by date of illness onset to analyze its space-time clustering using the ESRI® Geographic Information System (GIS) software ArcMap™ 10.1 and SatScan. Results: Based on active surveillance data, the distribution map of H7N9 cases shows that compared to the rest of China, the areas …


The Uncertain Climate Footprint Of Wetlands Under Human Pressure, Ana Maria Roxana Petrescu, Annalea Lohila, Juha-Pekka Tuovinen, Dennis D. Baldocchi, Ankur R. Desai, Nigel T. Roulet, Timo Vesala, Albertus Johannes Dolman, Walter C. Oechel, Barbara Marcolla, Thomas Friborg, Janne Rinne, Jaclyn Hatala Matthes, Lutz Merbold, Ana Meijide, Gerard Kiely, Matteo Sottocornola, Torsten Sachs, Donatella Zona, Andrej Varlagin, Derrick Y.F. Lai, Elmar Veenendaal, Frans-Jan W. Parmentier, Ute Skiba, Magnus Land, Arjan Hensen, Jacobus Van Huissteden, Lawrence B. Flanagan, Narasinha J. Shurpali, Thomas Grünwald, Elyn R. Humphreys, Marcin Jackowicz-Korczynski, Mika A. Aurela, Tuomas Laurila, Carsten Grüning, Chiara A.R. Corradi, Arina P. Schrier-Uijl, Torben R. Christensen, Mikkel P. Tamstorf, Mikhail Mastepanov, Pertti J. Martikainen, Shashi Verma, Christian Bernhofer, Alessandro Cescatti Jan 2015

The Uncertain Climate Footprint Of Wetlands Under Human Pressure, Ana Maria Roxana Petrescu, Annalea Lohila, Juha-Pekka Tuovinen, Dennis D. Baldocchi, Ankur R. Desai, Nigel T. Roulet, Timo Vesala, Albertus Johannes Dolman, Walter C. Oechel, Barbara Marcolla, Thomas Friborg, Janne Rinne, Jaclyn Hatala Matthes, Lutz Merbold, Ana Meijide, Gerard Kiely, Matteo Sottocornola, Torsten Sachs, Donatella Zona, Andrej Varlagin, Derrick Y.F. Lai, Elmar Veenendaal, Frans-Jan W. Parmentier, Ute Skiba, Magnus Land, Arjan Hensen, Jacobus Van Huissteden, Lawrence B. Flanagan, Narasinha J. Shurpali, Thomas Grünwald, Elyn R. Humphreys, Marcin Jackowicz-Korczynski, Mika A. Aurela, Tuomas Laurila, Carsten Grüning, Chiara A.R. Corradi, Arina P. Schrier-Uijl, Torben R. Christensen, Mikkel P. Tamstorf, Mikhail Mastepanov, Pertti J. Martikainen, Shashi Verma, Christian Bernhofer, Alessandro Cescatti

School of Natural Resources: Faculty Publications

Significant climate risks are associated with a positive carbon–temperature feedback in northern latitude carbon-rich ecosystems,making an accurate analysis of human impacts on the net greenhouse gas balance of wetlands a priority. Here, we provide a coherent assessment of the climate footprint of a network of wetland sites based on simultaneous and quasi-continuous ecosystem observations of CO2 and CH4 fluxes. Experimental areas are located both in natural and in managed wetlands and cover a wide range of climatic regions, ecosystem types, and management practices. Based on direct observations we predict that sustained CH4 emissions in natural ecosystems are …


Mercury Speciation, Retention, And Abundance Of Genes Involved With Mercury Methylation In Fertilized Salt Marsh Sediments, Caroline Collins Jan 2015

Mercury Speciation, Retention, And Abundance Of Genes Involved With Mercury Methylation In Fertilized Salt Marsh Sediments, Caroline Collins

Biology Honors Papers

Mercury (Hg) is a global pollutant which exists in both aquatic and terrestrial systems in three main forms including elemental Hg, ionic mercury, and methyl mercury, (MeHg), and Hg cycling plays an important role in ecosystems. Great Sippewisset Marsh, (GSM) in Falmouth MA has been chronically treated with fertilizer that contains heavy metals such as Hg in varying concentrations since the early 1970s and provides for an excellent location to study Hg contamination. The overall goal of this study is to analyze the key geochemical and microbial conditions that lead to MeHg production in the presence of the applied fertilizer. …


Association Between Respiratory Syncytial Virus Activity And Pneumococcal Disease In Infants: A Time Series Analysis Of Us Hospitalization Data., Daniel M. Weinberger, Keith P. Klugman, Claudia A. Steiner, Lone Simonsen, Cécile Viboud Jan 2015

Association Between Respiratory Syncytial Virus Activity And Pneumococcal Disease In Infants: A Time Series Analysis Of Us Hospitalization Data., Daniel M. Weinberger, Keith P. Klugman, Claudia A. Steiner, Lone Simonsen, Cécile Viboud

Epidemiology Faculty Publications

BACKGROUND:

The importance of bacterial infections following respiratory syncytial virus (RSV) remains unclear. We evaluated whether variations in RSV epidemic timing and magnitude are associated with variations in pneumococcal disease epidemics and whether changes in pneumococcal disease following the introduction of seven-valent pneumococcal conjugate vaccine (PCV7) were associated with changes in the rate of hospitalizations coded as RSV.

METHODS AND FINDINGS:

We used data from the State Inpatient Databases (Agency for Healthcare Research and Quality), including >700,000 RSV hospitalizations and >16,000 pneumococcal pneumonia hospitalizations in 36 states (1992/1993-2008/2009). Harmonic regression was used to estimate the timing of the average seasonal …


Estimating Relative Sea-Level Rise And Submergence Potential At A Coastal Wetland, Donald R. Cahoon Jan 2015

Estimating Relative Sea-Level Rise And Submergence Potential At A Coastal Wetland, Donald R. Cahoon

United States Geological Survey: Staff Publications

A tide gauge records a combined signal of the vertical change (positive or negative) in the level of both the sea and the land to which the gauge is affixed; or relative sealevel change, which is typically referred to as relative sea-level rise (RSLR). Complicating this situation, coastal wetlands exhibit dynamic surface elevation change (both positive and negative), as revealed by surface elevation table (SET) measurements, that is not recorded at tide gauges. Because the usefulness of RSLR is in the ability to tie the change in sea level to the local topography, it is important that RSLR be calculated …


Masked Expression Of Life- History Traits In A Highly Variable Environment, Jason A. Deboer, Joseph J. Fontaine, Christopher J. Chizinski, Kevin L. Pope Jan 2015

Masked Expression Of Life- History Traits In A Highly Variable Environment, Jason A. Deboer, Joseph J. Fontaine, Christopher J. Chizinski, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation oft en inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that diff er in environmental variability (i.e., annual …


A Systematic Review And Meta-Regression Analysis Of Lung Cancer Risk And Inorganic Arsenic In Drinking Water., Steven H. Lamm, Hamid Ferdosi, Elisabeth K. Dissen, Ji Li, Jaeil Ahn Jan 2015

A Systematic Review And Meta-Regression Analysis Of Lung Cancer Risk And Inorganic Arsenic In Drinking Water., Steven H. Lamm, Hamid Ferdosi, Elisabeth K. Dissen, Ji Li, Jaeil Ahn

Epidemiology Faculty Publications

High levels (> 200 µg/L) of inorganic arsenic in drinking water are known to be a cause of human lung cancer, but the evidence at lower levels is uncertain. We have sought the epidemiological studies that have examined the dose-response relationship between arsenic levels in drinking water and the risk of lung cancer over a range that includes both high and low levels of arsenic. Regression analysis, based on six studies identified from an electronic search, examined the relationship between the log of the relative risk and the log of the arsenic exposure over a range of 1-1000 µg/L. The …


Feeding Ecology And Habitat Utilization Of The Great Barracuda Sphyraena Barracuda (Edwards 1771) In Southeast Florida, Noah R. Hansen Jan 2015

Feeding Ecology And Habitat Utilization Of The Great Barracuda Sphyraena Barracuda (Edwards 1771) In Southeast Florida, Noah R. Hansen

HCNSO Student Theses and Dissertations

Great barracuda Sphyraena barracuda is a large predatory teleost found circumglobally, other than the Eastern Pacific Ocean. The species is commonly caught by both recreational and commercial fishermen as bycatch while targeting other, more economically or recreationally valuable fishes. This species also exhibits an ontogenetic shift in habitat, with juveniles inhabiting mangrove and seagrass habitats, while adults live near offshore reefs and associated structure.

This thesis consists of two separate studies of S. barracuda: 1) feeding ecology along an ontogenetic gradient and 2) habitat utilization of as derived through electronic tagging. The first chapter of this thesis describes the …


Sea Level And Turbidity Controls On Mangrove Soil Surface Elevation Change, Catherine E. Lovelock, Maria Fernanda Adame, Vicki Bennion, Matthew Hayes, Ruth Reef, Nadia Santini, Donald R. Cahoon Jan 2015

Sea Level And Turbidity Controls On Mangrove Soil Surface Elevation Change, Catherine E. Lovelock, Maria Fernanda Adame, Vicki Bennion, Matthew Hayes, Ruth Reef, Nadia Santini, Donald R. Cahoon

United States Geological Survey: Staff Publications

Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of …