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Articles 61 - 90 of 269
Full-Text Articles in Entire DC Network
Quantifying Amphibian Range Fragmentation In The Southeastern United States, Catherine E. Newman, Christopher C. Austin
Quantifying Amphibian Range Fragmentation In The Southeastern United States, Catherine E. Newman, Christopher C. Austin
Faculty Publications
© the authors. An often overlooked component of research on factors that drive amphibian geographic distributions is description of species range shape. Broad-scale range disjunction has implications for phylogeography, ecology, and conservation, but descriptions of fragmentation are usually based on subjective visual assessment of range maps. Here, we describe a method for objectively quantifying range fragmentation and use this method to describe the patterns of amphibian species range shapes in the southeastern United States, home to the highest amphibian species richness in North America. Species ranges varied widely in degree of fragmentation, from completely contiguous to highly fragmented, and degree …
An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn
An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn
LSU Master's Theses
Growth models estimate life history parameters that are used in the management of fisheries stocks. The most commonly used growth model in fisheries is the von Bertalanffy growth model (VBGM), yet it has been shown to provide a poor fit for length-at-age data of some species and other models exist. I reviewed 196 peer-reviewed age and growth studies and 50 NOAA stock assessments to examine temporal trends in the use of growth models and model selection in fisheries. I found that the use of multi-model frameworks has increased since the year 2000 and information theoretic approaches are replacing goodness-of-fit and …
Advancing Dendrochronological Studies Of Fire In The United States, Grant L. Harley, Christopher H. Baisan, Peter M. Brown, Donald A. Falk, William T. Flatley, Henri D. Grissino-Mayer, Amy Hessl, Emily K. Heyerdahl, Margot W. Kaye, Charles W. Lafon, Ellis Q. Margolis, R. Stockton Maxwell, Adam T. Naito, William J. Platt, Monica T. Rother, Thomas Saladyga, Rosemary L. Sherriff, Lauren A. Stachowiak, Michael C. Stambaugh, Elaine Kennedy Sutherland, Alan H. Taylor
Advancing Dendrochronological Studies Of Fire In The United States, Grant L. Harley, Christopher H. Baisan, Peter M. Brown, Donald A. Falk, William T. Flatley, Henri D. Grissino-Mayer, Amy Hessl, Emily K. Heyerdahl, Margot W. Kaye, Charles W. Lafon, Ellis Q. Margolis, R. Stockton Maxwell, Adam T. Naito, William J. Platt, Monica T. Rother, Thomas Saladyga, Rosemary L. Sherriff, Lauren A. Stachowiak, Michael C. Stambaugh, Elaine Kennedy Sutherland, Alan H. Taylor
Faculty Publications
© 2018 by the authors. Licensee MDPI, Basel, Switzerland. Dendroecology is the science that dates tree rings to their exact calendar year of formation to study processes that influence forest ecology (e.g., Speer 2010 [1], Amoroso et al., 2017 [2]). Reconstruction of past fire regimes is a core application of dendroecology, linking fire history to population dynamics and climate effects on tree growth and survivorship. Since the early 20th century when dendrochronologists recognized that tree rings retained fire scars (e.g., Figure 1), and hence a record of past fires, they have conducted studies worldwide to reconstruct [2] the historical range …
Micropaleontological Record Of A Preserved, Late Pleistocene Bald Cypress Forest On The Northern Gulf Of Mexico Inner Shelf, Jonathan Thien Truong
Micropaleontological Record Of A Preserved, Late Pleistocene Bald Cypress Forest On The Northern Gulf Of Mexico Inner Shelf, Jonathan Thien Truong
LSU Master's Theses
A cluster of previously buried Taxodium distichum stumps are exposed and preserved in growth position at the bottom of a trough on the inner Gulf of Mexico (GOM) continental shelf in 18 m water depth and 13 km offshore Orange Beach, AL. Radiocarbon ages from wood and optically stimulated luminescence (OSL) dating of sediments suggest a Marine Isotope Stage (MIS) 3 age, or older. This study builds on the previous work of Gonzalez (2018) and Obeclz (2017). Five biofacies were identified in vibracore collected in 2015 and 2016: 1) the Holocene Mississippi-Alabama-Florida (MAFLA) sand sheet, 2) a Holocene interbedded sand …
Linguistic Political Ecology With The Ngäbe Indigenous People Of Panama, Ginés A. Sánchez Arias
Linguistic Political Ecology With The Ngäbe Indigenous People Of Panama, Ginés A. Sánchez Arias
LSU Doctoral Dissertations
Indigenous communities from all corners of the globe live in uncertain times. From the vantage point of their “remote" lands, they undergo some of globalization’s most harmful externalities. Their homes become increasingly harder to maintain as extractive industries, development schemes, clandestine land grabs, and national bureaucracies encroach creating new colonial lands. First by assimilation, and then integration, these processes systematically undermine indigenous culture and autonomy. In place of such destructive coloniality, indigenous societies shelter unique ecological and linguistic knowledge that continues to serve their progress. This research applies lessons learned from studying with Ngäbe communities of western Panama, towards a …
Coupled Effects Of Oil Spill And Hurricane On Saltmarsh Terrestrial Arthropods, Wokil Bam, Linda M. Hooper-Bui, Rachel M. Strecker, Puspa L. Adhikari, Edward B. Overton
Coupled Effects Of Oil Spill And Hurricane On Saltmarsh Terrestrial Arthropods, Wokil Bam, Linda M. Hooper-Bui, Rachel M. Strecker, Puspa L. Adhikari, Edward B. Overton
Faculty Publications
Terrestrial arthropods play an important role in saltmarsh ecosystems, mainly affecting the saltmarsh’s primary production as the main consumers of terrestrial primary production and decomposition. Some of these arthropods, including selected insects and spiders, can be used as ecological indicators of overall marsh environmental health, as they are differentially sensitive to ecological stressors, such as land loss, erosion, oil spills, and tropical storms. In the present study, we used terrestrial arthropods collected from seven (three lightly-oiled, four heavily-oiled) sites in Barataria Bay and from three unoiled reference sites in Delacroix, Louisiana, to determine the impacts of the distribution and re-distribution …
Swing Voting In The 2016 Presidential Election In Counties Where Midlife Mortality Has Been Rising In White Non-Hispanic Americans, Usama Bilal, Emily A. Knapp, Richard S. Cooper
Swing Voting In The 2016 Presidential Election In Counties Where Midlife Mortality Has Been Rising In White Non-Hispanic Americans, Usama Bilal, Emily A. Knapp, Richard S. Cooper
Faculty Publications
Understanding the effects of widespread disruption of the social fabric on public health outcomes can provide insight into the forces that drive major political realignment. Our objective was to estimate the association between increases in mortality in middle-aged non-Hispanic white adults from 1999 to 2005 to 2009–2015, health inequalities in life expectancy by income, and the surge in support for the Republican Party in pivotal US counties in the 2016 presidential election. We conducted a longitudinal ecological study in 2764 US counties from 1999 to 2016. Increases in mortality were measured using age-specific (45–54 years of age) all-cause mortality from …
An Annotated List Of Auchenorrhyncha And Heteroptera Collected In The Coastal Salt Marshes Of The Mississippi Delta In Louisiana, I. M. Sokolov, X. Chen, R. M. Strecker, L. M. Hooper-Bùi
An Annotated List Of Auchenorrhyncha And Heteroptera Collected In The Coastal Salt Marshes Of The Mississippi Delta In Louisiana, I. M. Sokolov, X. Chen, R. M. Strecker, L. M. Hooper-Bùi
Faculty Publications
Insects that live in the saltwater and brackish marshes, which fringe the northern coast of the Gulf of Mexico, are largely unstudied. During 2011-2013, a survey of insect fauna of the coastal salt marshes of the Mississippi Delta in Louisiana was conducted. We present the species of terrestrial representatives of Heteroptera and Auchenorrhyncha collected during that study. The Auchenorrhyncha are represented by 33 species in 6 families, with Cicadellidae (16 species) and Delphacidae (13 spp.), and are the most diverse. The terrestrial heteropterans are represented by 11 species in 5 families with the majority of species in Miridae (6 spp.). …
Repeated Evolution Of Vertebrate Pollination Syndromes In A Recently Diverged Andean Plant Clade, Laura P. Lagomarsino, Elisabeth J. Forrestel, Nathan Muchhala, Charles C. Davis
Repeated Evolution Of Vertebrate Pollination Syndromes In A Recently Diverged Andean Plant Clade, Laura P. Lagomarsino, Elisabeth J. Forrestel, Nathan Muchhala, Charles C. Davis
Faculty Publications
© 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution. Although specialized interactions, including those involving plants and their pollinators, are often invoked to explain high species diversity, they are rarely explored at macroevolutionary scales. We investigate the dynamic evolution of hummingbird and bat pollination syndromes in the centropogonid clade (Lobelioideae: Campanulaceae), an Andean-centered group of ∼550 angiosperm species. We demonstrate that flowers hypothesized to be adapted to different pollinators based on flower color fall into distinct regions of morphospace, and this is validated by morphology of species with known pollinators. This supports the existence of …
Economic Growth And Mortality: Do Social Protection Policies Matter?, Usama Bilal, Richard Cooper, Francis Abreu, Claudia Nau, Manuel Franco, Thomas A. Glass
Economic Growth And Mortality: Do Social Protection Policies Matter?, Usama Bilal, Richard Cooper, Francis Abreu, Claudia Nau, Manuel Franco, Thomas A. Glass
Faculty Publications
Background: In the 20th century, periods of macroeconomic growth have been associated with increases in population mortality. Factors that cause or mitigate this association are not well understood. Evidence suggests that social policy may buffer the deleterious impact of economic growth. We sought to explore associations between changing unemployment (as a proxy for economic change) and trends in mortality over 30 years in the context of varying social protection expenditures. Methods: We model change in all-cause mortality in 21 OECD (Organization for Economic Cooperation and Development) countries from 1980 to 2010. Data from the Comparative Welfare States Data Set and …
Bacteria Associated With Piezodorus Guildinii (Hemiptera: Pentatomidae), With Special Reference To Those Transmitted By Feeding, Claudia Husseneder, Jong Seok Park, Andrea Howells, Chinmay V. Tikhe, Jeffrey A. Davis
Bacteria Associated With Piezodorus Guildinii (Hemiptera: Pentatomidae), With Special Reference To Those Transmitted By Feeding, Claudia Husseneder, Jong Seok Park, Andrea Howells, Chinmay V. Tikhe, Jeffrey A. Davis
Faculty Publications
The redbanded stink bug, Piezodorus guildinii (Westwood) (Hemiptera: Heteroptera: Pentatomidae), is a rapidly growing pest damaging southern US agriculture. Pentatomid stink bugs are known to vector bacterial, fungal, and viral plant diseases. However, bacteria associated with redbanded stink bugs and their vector potential have not yet been assessed. In this study, we 1) cultured and identified bacteria transmitted by feeding of redbanded stink bug and 2) described bacteria from guts of redbanded stink bug individuals using next-generation sequencing of 16S rRNA genes. Nineteen bacteria transmitted by feeding of redbanded stink bug on soybean agar were isolated and identified via Sanger …
Diabetes Prevalence Is Associated With Different Community Factors In The Diabetes Belt Versus The Rest Of The United States, Candice A. Myers, Tim Slack, Stephanie T. Broyles, Steven B. Heymsfield, Timothy S. Church, Corby K. Martin
Diabetes Prevalence Is Associated With Different Community Factors In The Diabetes Belt Versus The Rest Of The United States, Candice A. Myers, Tim Slack, Stephanie T. Broyles, Steven B. Heymsfield, Timothy S. Church, Corby K. Martin
Faculty Publications
Objective: To investigate differences in community characteristics associated with diabetes prevalence between the Diabetes Belt and the rest of the contiguous United States (U.S.). Methods: County-level adult diabetes prevalence estimates (i.e., percent of people [≥20 years] with diagnosed diabetes 2009) were used from the Centers for Disease Control and Prevention, in addition to data from the U.S. Census Bureau, U.S. Department of Agriculture, and U.S. Department of Health and Human Services, to carry out a spatial regime analysis to identify county-level factors correlated with diabetes prevalence in the Diabetes Belt versus the remainder of the U.S. Results: Counties outside of …
Introduction, Victor H. Rivera-Monroy, Erik Kristensen, Shing Yip Lee, Robert R. Twilley
Introduction, Victor H. Rivera-Monroy, Erik Kristensen, Shing Yip Lee, Robert R. Twilley
Faculty Publications
One of the major issues we currently need to address in mangrove ecological research is the causes (qualitative and quantitative) that drive current mismanagement and degradation of mangrove wetlands; one of the most productive and valuable coastal ecosystems in the world. This is a complex task, and we need to consider the complex interactions between social and ecological systems, including an evaluation of state-of-the-art mangrove ecosystem science. For instance, the attempts to refine and improve the significance of mangrove wetlands’ economic value include not only the most visible and well-recognized mangrove ecosystem services around the world, e.g., fisheries and wood …
Mangrove Ecosystems: A Global Biogeographic Perspective: Structure, Function, And Services, Victor H. Rivera-Monroy, Erik Kristensen, Shing Yip Lee, Robert R. Twilley
Mangrove Ecosystems: A Global Biogeographic Perspective: Structure, Function, And Services, Victor H. Rivera-Monroy, Erik Kristensen, Shing Yip Lee, Robert R. Twilley
Faculty Publications
This book presents a comprehensive overview and analysis of mangrove ecological processes, structure, and function at the local, biogeographic, and global scales and how these properties interact to provide key ecosystem services to society. The analysis is based on an international collaborative effort that focuses on regions and countries holding the largest mangrove resources and encompasses the major biogeographic and socio-economic settings of mangrove distribution. Given the economic and ecological importance of mangrove wetlands at the global scale, the chapters aim to integrate ecological and socio-economic perspectives on mangrove function and management using a system-level hierarchical analysis framework. The book …
Combining Biodiversity Resurveys Across Regions To Advance Global Change Research, Kris Verheyen, Pieter De Frenne, Lander Baeten, Donald M. Waller, Radim Hédl, Michael P. Perring, Haben Blondeel, Jörg Brunet, Markéta Chudomelová, Guillaume Decocq, Emiel De Lombaerde, Leen Depauw, Thomas Dirnböck, Tomasz Durak, Ove Eriksson, Frank S. Gilliam, Thilo Heinken, Steffi Heinrichs, Martin Hermy, Bogdan Jaroszewicz, Michael A. Jenkins, Sarah E. Johnson, Keith J. Kirby, Martin Kopecký, Dries Landuyt, Jonathan Lenoir, Daijiang Li, Martin Macek, Sybryn L. Maes, František Máliš, Fraser J.G. Mitchell, Tobias Naaf, George Peterken
Combining Biodiversity Resurveys Across Regions To Advance Global Change Research, Kris Verheyen, Pieter De Frenne, Lander Baeten, Donald M. Waller, Radim Hédl, Michael P. Perring, Haben Blondeel, Jörg Brunet, Markéta Chudomelová, Guillaume Decocq, Emiel De Lombaerde, Leen Depauw, Thomas Dirnböck, Tomasz Durak, Ove Eriksson, Frank S. Gilliam, Thilo Heinken, Steffi Heinrichs, Martin Hermy, Bogdan Jaroszewicz, Michael A. Jenkins, Sarah E. Johnson, Keith J. Kirby, Martin Kopecký, Dries Landuyt, Jonathan Lenoir, Daijiang Li, Martin Macek, Sybryn L. Maes, František Máliš, Fraser J.G. Mitchell, Tobias Naaf, George Peterken
Faculty Publications
More and more ecologists have started to resurvey communities sampled in earlier decades to determine long-term shifts in community composition and infer the likely drivers of the ecological changes observed. However, to assess the relative importance of and interactions among multiple drivers, joint analyses of resurvey data from many regions spanning large environmental gradients are needed. In this article, we illustrate how combining resurvey data from multiple regions can increase the likelihood of driver orthogonality within the design and show that repeatedly surveying across multiple regions provides higher representativeness and comprehensiveness, allowing us to answer more completely a broader range …
Condition Of Birds In Amazonian Rainforest Fragments And Second-Growth Forests, Angelica Maria Hernandez Palma
Condition Of Birds In Amazonian Rainforest Fragments And Second-Growth Forests, Angelica Maria Hernandez Palma
LSU Doctoral Dissertations
Deforestation modifies otherwise intact expanses of forest into small, isolated fragments. In addition to fragmentation, deforestation also creates abrupt forest edges and large areas of regenerating vegetation where land is abandoned after clearing. Understanding how changes in the landscape affect the physical condition of birds is crucial for managing populations in human-modified landscapes. Here I use the biomarkers feather growth rate and feather quality (ptilochronology), fluctuating asymmetry (FA), and stress hormones from feathers (CORT), to estimate the physical condition of Amazonian understory birds living in forest fragments, second-growth forests, and continuous forests. Feather CORT revealed how fragmentation disrupts interspecific interactions; …
Human Gut Microbiota And Obesity: How Is Gut Microbiota Associated With Obesity Improvement Induced By Bariatric Surgeries Or Low-Calorie Diet Treatment?, Rui Zhang
LSU Doctoral Dissertations
An increasing number of studies suggest that the complex microbial community of the human gut may have an important role in human health and disease conditions such as obesity and diabetes. However, the causal relationship among gut microbiota, obesity, weight loss, and the influence of bariatric surgery remains largely unknown. This study investigated the correlation between human gut microbiota and obesity via determining how gut microbiota is associated with obesity improvement induced by bariatric surgeries (BRS) and low-calorie diet (LCD) treatment. Specifically, we investigated the effects of various bariatric surgery (BRS) procedures and a low-calorie diet (LCD) treatment on the …
Isolation And Characterization Of Acidobacterium Ailaaui Sp. Nov., A Novel Member Of Acidobacteria Subdivision 1, From A Geothermally Heated Hawaiian Microbial Mat, Marisa R. Myers, G. M. King
Isolation And Characterization Of Acidobacterium Ailaaui Sp. Nov., A Novel Member Of Acidobacteria Subdivision 1, From A Geothermally Heated Hawaiian Microbial Mat, Marisa R. Myers, G. M. King
Faculty Publications
© 2016 IUMS. A novel member of Acidobacteria was isolated from a microbial mat growing on a geothermally heated dead tree trunk in Hawai'i Volcanoes National Park (HI, USA). The rod-shaped, Gramnegative capsulated cells of strain PMMR2T were non-motile and catalase and oxidase negative. Growth occurred aerobically from 15 to 55 °C (optimum, 40 °C) and at pH values from 4.5 to 7.0 (optimum, 6.5). A limited range of sugars and organic acids supported growth. However, results of a genomic analysis suggested that various polysaccharides might be hydrolysed as carbon sources, and evidence for pectin degradation was observed in liquid …
Association Between 25-Hydroxyvitamin D And Intact Parathyroid Hormone Levels Across Latitude Among Adults With African Ancestry, Holly Kramer, Pauline Camacho, John Aloia, Amy Luke, Pascal Bovet, Jacob Plange Rhule, Terrence Forrester, Vickie Lambert, Regina Harders, Lara Dugas, Richard Cooper, Ramon Durazo-Arvizu
Association Between 25-Hydroxyvitamin D And Intact Parathyroid Hormone Levels Across Latitude Among Adults With African Ancestry, Holly Kramer, Pauline Camacho, John Aloia, Amy Luke, Pascal Bovet, Jacob Plange Rhule, Terrence Forrester, Vickie Lambert, Regina Harders, Lara Dugas, Richard Cooper, Ramon Durazo-Arvizu
Faculty Publications
Objective: To compare levels of 25-hydroxyvitamin D (25OHD) associated with a plateauing of intact parathyroid (iPTH) across latitudes among adults with African ancestry. Methods: This study included approximately 500 adults of African ancestry ages 25 to 45 years living in 4 sites: Chicago, Illinois (41°N), Jamaica (17°N), Ghana (6°N), and South Africa (34°S). Multivariate linear regression models, a nonlinear logistic growth curve model, and piecewise linear models with a single knot were fitted to estimate the 25OHD level associated with a plateauing of iPTH with adjustment for covariates. Goodness of fit was compared using computer intensive permutation tests. Results: Mean …
Influence Of The Mississippi River On Pseudo-Nitzschia Spp. Abundance And Toxicity In Louisiana Coastal Waters, Sibel Bargu, Melissa M. Baustian, Nancy N. Rabalais, Ross Del Rio, Benjamin Von Korff, R. Eugene Turner
Influence Of The Mississippi River On Pseudo-Nitzschia Spp. Abundance And Toxicity In Louisiana Coastal Waters, Sibel Bargu, Melissa M. Baustian, Nancy N. Rabalais, Ross Del Rio, Benjamin Von Korff, R. Eugene Turner
Faculty Publications
The presence of domoic acid (DA) toxin from multiple species of Pseudo-nitzschia is a concern in the highly productive food webs of the northern 1,* 2,3 2 1 1,4 1 1 2 3 4 Gulf of Mexico. We documented the Pseudo-nitzschia presence, abundance, blooms, and toxicity over 3 years along a transect ∼100 km west of the Mississippi River Delta on the continental shelf. Pseudo-nitzschia were present throughout the year and occurred in high abundances (>10 cells l ) in the early spring months during high Mississippi River (MSR) flow (∼20,000 m s ) but were most abundant ( …
Variable Prey Development Time Suppresses Predator-Prey Cycles And Enhances Stability, James T. Cronin, John D. Reeve, Dashun Xu, Mingqing Xiao, Heidi N. Stevens
Variable Prey Development Time Suppresses Predator-Prey Cycles And Enhances Stability, James T. Cronin, John D. Reeve, Dashun Xu, Mingqing Xiao, Heidi N. Stevens
Faculty Publications
© 2016 John Wiley & Sons Ltd/CNRS. Although theoretical models have demonstrated that predator-prey population dynamics can depend critically on age (stage) structure and the duration and variability in development times of different life stages, experimental support for this theory is non-existent. We conducted an experiment with a host-parasitoid system to test the prediction that increased variability in the development time of the vulnerable host stage can promote interaction stability. Host-parasitoid microcosms were subjected to two treatments: Normal and High variance in the duration of the vulnerable host stage. In control and Normal-variance microcosms, hosts and parasitoids exhibited distinct population …
Competition-Mediated Feedbacks In Experimental Multispecies Epizootics, Tad Dallas, Richard J. Hall, John M. Drake
Competition-Mediated Feedbacks In Experimental Multispecies Epizootics, Tad Dallas, Richard J. Hall, John M. Drake
Faculty Publications
© 2016 by the Ecological Society of America. Competition structures ecological communities and alters host-pathogen interactions. In environmentally transmitted pathogens, an infection-resistant competitor may influence infection dynamics in a susceptible species through the negative impacts of competition (e.g., by reducing host density or causing nutritional stress that increases susceptibility to infection) and/or the positive impacts of reducing transmission efficiency (e.g., by removing environmental pathogen stages). Thus, a non-susceptible competitor may enhance, reduce, or have no net effect on susceptible host density and infection prevalence. Here, we couple an epidemiological model with experimental epidemics to test how resource competition with a …
Constrained Total Energy Expenditure And Metabolic Adaptation To Physical Activity In Adult Humans, Herman Pontzer, Ramon Durazo-Arvizu, Lara R. Dugas, Jacob Plange-Rhule, Pascal Bovet, Terrence E. Forrester, Estelle V. Lambert, Richard S. Cooper, Dale A. Schoeller, Amy Luke
Constrained Total Energy Expenditure And Metabolic Adaptation To Physical Activity In Adult Humans, Herman Pontzer, Ramon Durazo-Arvizu, Lara R. Dugas, Jacob Plange-Rhule, Pascal Bovet, Terrence E. Forrester, Estelle V. Lambert, Richard S. Cooper, Dale A. Schoeller, Amy Luke
Faculty Publications
Current obesity prevention strategies recommend increasing daily physical activity, assuming that increased activity will lead to corresponding increases in total energy expenditure and prevent or reverse energy imbalance and weight gain [1-3]. Such Additive total energy expenditure models are supported by exercise intervention and accelerometry studies reporting positive correlations between physical activity and total energy expenditure [4] but are challenged by ecological studies in humans and other species showing that more active populations do not have higher total energy expenditure [5-8]. Here we tested a Constrained total energy expenditure model, in which total energy expenditure increases with physical activity at …
Change In Obesity Prevalence Across The United States Is Influenced By Recreational And Healthcare Contexts, Food Environments, And Hispanic Populations, Candice A. Myers, Tim Slack, Corby K. Martin, Stephanie T. Broyles, Steven B. Heymsfield
Change In Obesity Prevalence Across The United States Is Influenced By Recreational And Healthcare Contexts, Food Environments, And Hispanic Populations, Candice A. Myers, Tim Slack, Corby K. Martin, Stephanie T. Broyles, Steven B. Heymsfield
Faculty Publications
Objective To examine change in county-level adult obesity prevalence between 2004 and 2009 and identify associated community characteristics. Methods Change in county-level adult (≥20 years) obesity prevalence was calculated for a 5-year period (2004-2009). Community measures of economic, healthcare, recreational, food environment, population structure, and education contexts were also calculated. Regression analysis was used to assess community characteristics associated (p< 0.01) with change in adult obesity prevalence. Results Mean±SD change in obesity prevalence was 5.1±2.4%. Obesity prevalence decreased in 1.4% (n = 44) and increased in 98% (n = 3,060) of counties from 2004-2009. Results showed that both baseline levels and increases in physically inactive adults were associated with greater increases in obesity prevalence, while baseline levels of and increases in physician density and grocery store/supercenter density were related to smaller increases in obesity rates. Baseline levels of the Hispanic population share were negatively linked to changing obesity levels, while places with greater Hispanic population growth saw greater increases in obesity. Conclusions Most counties in the U.S. experienced increases in adult obesity prevalence from 2004 to 2009. Findings suggest that community-based interventions targeting adult obesity need to incorporate a range of community factors, such as levels of physical inactivity, access to physicians, availability of food outlets, and ethnic/racial population composition.
Halobacteriovorax, An Underestimated Predator On Bacteria: Potential Impact Relative To Viruses On Bacterial Mortality, Henry N. Williams, Despoina S. Lymperopoulou, Rana Athar, Ashvini Chauhan, Tamar L. Dickerson, Huan Chen, Edward Laws, Timkhite Kulu Berhane, Adrienne R. Flowers, Nadine Bradley, Shanterial Young, Denene Blackwood, Jacqueline Murray, Oladipupo Mustapha, Cory Blackwell, Yahsuan Tung, Rachel T. Noble
Halobacteriovorax, An Underestimated Predator On Bacteria: Potential Impact Relative To Viruses On Bacterial Mortality, Henry N. Williams, Despoina S. Lymperopoulou, Rana Athar, Ashvini Chauhan, Tamar L. Dickerson, Huan Chen, Edward Laws, Timkhite Kulu Berhane, Adrienne R. Flowers, Nadine Bradley, Shanterial Young, Denene Blackwood, Jacqueline Murray, Oladipupo Mustapha, Cory Blackwell, Yahsuan Tung, Rachel T. Noble
Faculty Publications
Predation on bacteria and accompanying mortality are important mechanisms in controlling bacterial populations and recycling of nutrients through the microbial loop. The agents most investigated and seen as responsible for bacterial mortality are viruses and protists. However, a body of evidence suggests that predatory bacteria such as the Halobacteriovorax (formerly Bacteriovorax), a Bdellovibrio-like organism, contribute substantially to bacterial death. Until now, conclusive evidence has been lacking. The goal of this study was to better understand the contributors to bacterial mortality by addressing the poorly understood role of Halobacteriovorax and how their role compares with that of viruses. The results revealed …
Coloration In The Polymorphic Frog Oophaga Pumilio Associates With Level Of Aggressiveness In Intraspecific And Interspecific Behavioral Interactions, Sandra P. Galeano, Kyle E. Harms
Coloration In The Polymorphic Frog Oophaga Pumilio Associates With Level Of Aggressiveness In Intraspecific And Interspecific Behavioral Interactions, Sandra P. Galeano, Kyle E. Harms
Faculty Publications
© 2015, Springer-Verlag Berlin Heidelberg. Intraspecific morphological variation may correspond to behavioral variation that helps determine the nature of species interactions. Color variation among populations of variably toxic organisms has been shown to associate with alternative anti-predator behaviors. However, the effects of these alternative behavioral tendencies on the outcomes of interspecific interactions other than predator–prey remain largely unexplored. We investigated how coloration and body size variation in Oophaga pumilio, one of the most phenotypically diverse amphibians known, associated with territorial aggressiveness and how this association influenced the outcome of agonistic male–male interactions with conspecifics and heterospecifics of two sympatric species …
Evaluating Survival Of Released Ranched American Alligator In Coastal Louisiana, Kristy Durham Capelle
Evaluating Survival Of Released Ranched American Alligator In Coastal Louisiana, Kristy Durham Capelle
LSU Master's Theses
Since 1986, Louisiana’s American alligator (Alligator mississippiensis) ranching program has required the release of alligators produced from eggs collected from wild nests to maintain wild populations. This project assessed long-term harvest data (1991-2010s) to estimate survival of released alligators. First, wildlife and fishery harvest models and general inter-disciplinary survival models were evaluated to determine best fit to the data. Second, once the best fitting model was selected, release length, precipitation and temperature from release sites, and an index of hunter effort were added to investigate influences on survival estimates. Release length was included because over time the proportion and size …
Ant Diversity And Community Structure In Coastal Dunes And Wetlands, Xuan Chen
Ant Diversity And Community Structure In Coastal Dunes And Wetlands, Xuan Chen
LSU Doctoral Dissertations
How do many species live in a certain place? How does species composition changes among habitats? And what mechanisms decide species distribution? These are fundamental questions in community ecology. I first investigated ant diversity in two coastal ecosystems (dunes and wetlands) in the northern Gulf of Mexico, and then used the distribution patterns to infer assembly processes that structure ant communities in coastal areas. Specifically, the following hypotheses are tested: (1) coastal systems support lower ant diversity due to the unsuitable environment; (2) species living near the seashore are a subset of those exist near inland; (3) deterministic processes are …
Genetic Divergence Of An Avian Endemic On The Californian Channel Islands, Amy G. Wilson, Yvonne Chan, Sabrina S. Taylor, Peter Arcese
Genetic Divergence Of An Avian Endemic On The Californian Channel Islands, Amy G. Wilson, Yvonne Chan, Sabrina S. Taylor, Peter Arcese
Faculty Publications
The Californian Channel Islands are near-shore islands with high levels of endemism, but extensive habitat loss has contributed to the decline or extinction of several endemic taxa. A key parameter for understanding patterns of endemism and demography in island populations is the magnitude of inter-island dispersal. This paper estimates the extent of migration and genetic differentiation in three extant and two extinct populations of Channel Island song sparrows (Melospiza melodia graminea). Inter-island differentiation was substantial (G''ST: 0.14-0.37), with San Miguel Island having the highest genetic divergence and lowest migration rates. Santa Rosa and Santa Cruz Island populations were less diverged …
Directional Dominance On Stature And Cognition In Diverse Human Populations, Peter K. Joshi, Tonu Esko, Hannele Mattsson, Niina Eklund, Ilaria Gandin, Teresa Nutile, Anne U. Jackson, Claudia Schurmann, Albert V. Smith, Weihua Zhang, Yukinori Okada, Alena Stančáková, Jessica D. Faul, Wei Zhao, Traci M. Bartz, Maria Pina Concas, Nora Franceschini, Stefan Enroth, Veronique Vitart, Stella Trompet, Xiuqing Guo, Daniel I. Chasman, Jeffrey R. O'Connel, Tanguy Corre, Suraj S. Nongmaithem, Yuning Chen, Massimo Mangino, Daniela Ruggiero, Michela Traglia, Aliki Eleni Farmaki, Tim Kacprowski, Andrew Bjonnes, Ashley Van Der Spek
Directional Dominance On Stature And Cognition In Diverse Human Populations, Peter K. Joshi, Tonu Esko, Hannele Mattsson, Niina Eklund, Ilaria Gandin, Teresa Nutile, Anne U. Jackson, Claudia Schurmann, Albert V. Smith, Weihua Zhang, Yukinori Okada, Alena Stančáková, Jessica D. Faul, Wei Zhao, Traci M. Bartz, Maria Pina Concas, Nora Franceschini, Stefan Enroth, Veronique Vitart, Stella Trompet, Xiuqing Guo, Daniel I. Chasman, Jeffrey R. O'Connel, Tanguy Corre, Suraj S. Nongmaithem, Yuning Chen, Massimo Mangino, Daniela Ruggiero, Michela Traglia, Aliki Eleni Farmaki, Tim Kacprowski, Andrew Bjonnes, Ashley Van Der Spek
Faculty Publications
Homozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of …