Digital Commons Network^™

The Use Of Geospatial Modeling And Novel Diagnostics To Detect And Map Risk Factors Of Soil-Transmitted Helminths In Feira De Santana, Brazil, Ryan Harry Avery

LSU Doctoral Dissertations

Soil-transmitted helminth (STH) infections impact billions of people worldwide. The traditional STH control approach is a morbidity control strategy implementing mass drug administration (MDA) programs targeting school-aged children (SAC). In Brazil, this control strategy has decreased STH prevalence to less than 20% in most of the country and providing an opportunity to transition from the morbidity control program and towards a surveillance and response system geared towards STH elimination. Surveillance and response systems geared towards elimination require the implementation higher accuracy diagnostics to detect infection in low-transmission communities, surveillance of entire households, high-resolution modeling at the household-habitat scale, and targeted …

A Critical Edition Of The Bachianas Brasileiras Nº2 For Piano And Cello By Heitor Villa-Lobos, Henrique Borges Gomes

LSU Doctoral Dissertations

The Brazilian composer Heitor Villa-Lobos (1887-1959) is one of the most prominent names in Twentieth century music. His compositional scope encompasses languages that often combine national elements of Brazilian music with traditions of European music. Villa-Lobos’s Bachianas Brasileiras is one of the most representative works that reflect the dialogue of those distinct worlds. With this series of distinct pieces, Villa-Lobos aimed to achieve musical universality through incorporating elements of Bach’s music with that of his own, which was already permeated by Brazilian popular traditions.

This research focusses on the four movements of the “reduced” version of the Bachianas Brasileiras no.2 …

The Effects Of Tree Plantations And Land Use On Natural Regeneration Of Woody Plants In The Tropics: Diversity, Species Composition, Successional Dynamics, And Functional Traits, John Benjamin Longworth

LSU Doctoral Dissertations

As anthropogenic forests become more common in the tropics, there is a greater need to understand the factors that impact forest succession. I used censuses of woody plants in successional forests to study the effects of prior land use and tree plantations on species composition and richness. First, I tested the hypothesis that communities originating from different land uses were converging in species composition over time. I compared species composition using the Chao-Jaccard similarity index. I observed shifts in the dominant species during the first 30 years of succession, but not convergence of species composition in sites with different land-use …

Brazilian Surface And Upper-Level Wind Characteristics Based On Ground And Model Observations From 1980–2014, Joshua M. Gilliland

LSU Doctoral Dissertations

The examination of temporal changes in surface winds has been analyzed by scientists for a variety of physical, biological, climatological, and socioeconomic reasons. This research uses surface and upper-level wind data from historical in-situ and climate models to examine the geographical and climatological characteristics of wind across Brazil during 1980–2014. Overall linear and quantile regression shows that surface wind speed trends are changing regionally across Brazil. Wind speeds across northeastern Brazil are increasing, while a decreasing trend is documented for interior and southeastern Brazil. The spatial and temporal trends found are possibly related to alterations in the physical landscape (urbanization …

Exchange Rate Volatility Effects On Brics Countries Exports, David Isaias Maradiaga Pineda

LSU Doctoral Dissertations

The leaders of the leading emerging economies Brazil, Russia, India, China, and South Africa (BRICS) claim that increased currency exchange rate volatility (CERV) from USD, EUR, and JPY (G-3) negatively impacts their exports, and expressed their desire for less trade dependence on these currencies. The literature on the impact of CERV on trade is vast. However, no consensus on the impact’s direction and significance has been reached yet. The motivation of this study was: first, to contribute to the existing empirical literature by using an alternative methodology; and second, to provide empirical evidence to the claim’s validity or nullity by …

Structure And Organization Of Canopy Bird Assemblages In Lowland Neotropical Rainforests, David Lawrence Anderson

LSU Doctoral Dissertations

Although birds of the forest canopy are an important component of tropical forest ecosystems, difficulty accessing the forest canopy has limited the advancement of knowledge pertaining to this group of species. Here I test methods for the study of canopy birds in lowland Neotropical rainforests, and identify recurring patterns of community structure in canopy bird assemblages as well as processes potentially responsible for these patterns. I used three methods to assess differences in ground-based and canopy-based methods for detecting forest birds in a 100-ha plot of lowland rainforest in northern Honduras: (1) point counts from the ground; (2) repeat censuses …

The Effects Of Geomorphology And Primary Productivity On Neotropical Leaf Litter Herpetofauna: Implications For Amazonian Rainforest Conservation, Jessica L. Deichmann

LSU Doctoral Dissertations

The Amazon rainforest encompasses over one billion acres of South America and sustains remarkable biodiversity. Despite the large body of research stemming from this region, little is known about the effects of geomorphology and primary productivity on the fauna of Amazonia, and on reptiles and amphibians in particular. In my dissertation, I examine differences in the abundance, biomass and species richness of secondary consumers in the leaf litter herpetofauna communities on young and ancient soils. Herein, I develop methods to utilize existing data sets and museum collections in new studies involving community biomass. I found that, although the process of …

Tropical Pyramids: Dung Beetle Richness, Abundance, And Biomass, Meghan Gabrielle Radtke

LSU Doctoral Dissertations

Volume is a proxy for biomass in hard bodied arthropods (P < 0.0001). I constructed biomass-volume equations for Neotropical (P < 0.0001), temperate (P < 0.0001) and 12 Neotropical genera of scarabs, of which 11 were highly significant. The effect of short term (< 1 year) alcohol storage on volume was negligable. I found scarab volume on geologically old soils in the Amazon was one-third that of the geologically young Amazon (P < 0.0001). Species richness (P = 0.0002), Chao 1 (P = 0.0003), Fisher’s  (P = 0.008) and Margalef indices (P = 0.0003) were greater on young soils. Menhinick (P = 0.54), Simpson (P = 0.54) and rarefied species richness (P = 0.24), which correct for sample size differences, indicated no difference in diversity. Young Amazonian soils likely support a higher volume and abundance of scarabs than old soils, but diversity across Amazonia may be similar. I compared beta-diversity of scarab communities across Amazonia. Species rank-abundance curves did not differ among sites whereas volume-abundance distributions and volume-rank abundance curves indicated a larger range of scarab sizes in Brazil than Ecuador. At local levels (<62 km), communities were similar whereas at large distances (>1750 km), they were different. Differences between Brazil and Ecuador may be explained by varied soil age and productivity. I examined the effects of tropical forest fragmentation on scarabs, comparing my results with three other studies from the same site. Among 1, 10, and 100-ha fragments and continuous forest, I found two important trends; beetle biomass and species richness increased with fragment area per sampling effort. Comparing all four studies, diversity increased with fragment size, and by my rarefaction analyses, two studies demonstrated beetle volume increased with fragment size. …