Search Results

Spatial Mismatch Between Hiv Infection and Access to Hiv Service Facilities in Texas
Since 2004, the number of people living with HIV (PLWH) has steadily increased by about 5% and currently, the number in Texas is about 86,000. Though the National HIV/AIDS Strategic Plan seeks to ensure “unfettered access to quality healthcare”, barriers to access still exist especially among minority populations. This study examines the relationship between HIV infection rates and the geographic location of HIV service centers with a focus on 4 counties: namely, Dallas, Denton, Harris and Tarrant. The goal is to show whether there is a spatial mismatch between HIV rates and service providers. Are service facilities located in zip codes where they are most needed? Using the vulnerability framework and the Inverse Care Law (ICL), we address the research question using demographic variables (race/ethnicity, sex, poverty, education attainment) and HIV data. Our results show that extreme vulnerable zip codes have high HIV rates and closest proximity to HIV service providers.
A Spatially Explicit Environmental Health Surveillance Framework for Tick-Borne Diseases
In this paper, I will show how applying a spatially explicit context to an existing environmental health surveillance framework is vital for more complete surveillance of disease, and for disease prevention and intervention strategies. As a case study to test the viability of a spatial approach to this existing framework, the risk of human exposure to Lyme disease will be estimated. This spatially explicit framework divides the surveillance process into three components: hazard surveillance, exposure surveillance, and outcome surveillance. The components will be used both collectively and individually, to assess exposure risk to infected ticks. By utilizing all surveillance components, I will identify different areas of risk which would not have been identified otherwise. Hazard surveillance uses maximum entropy modeling and geographically weighted regression analysis to create spatial models that predict the geographic distribution of ticks in Texas. Exposure surveillance uses GIS methods to estimate the risk of human exposures to infected ticks, resulting in a map that predicts the likelihood of human-tick interactions across Texas, using LandScan 2008TM population data. Lastly, outcome surveillance uses kernel density estimation-based methods to describe and analyze the spatial patterns of tick-borne diseases, which results in a continuous map that reflects disease rates based on population location. Data for this study was obtained from the Texas Department of Health Services and the University of North Texas Health Science Center. The data includes disease data on Lyme disease from 2004-2008, and the tick distribution estimates are based on field collections across Texas from 2004-2008.
Western Spruce Budworm Effects on Throughfall C, N, and P Fluxes in a Central Washington Forest
Western spruce budworm (Choristoneura occidentalis) outbreaks periodically disturb Western US conifer forests by defoliating canopies, which could alter the quantity and chemistry of throughfall delivered to the forest floor. Our objectives were to: i) quantify throughfall water, carbon (C), nitrogen (N), and phosphorus (P) fluxes under budworm-impacted canopies, and ii) examine the influence of herbivore intensity on flux magnitudes. In June 2015, we installed throughfall collectors in two watersheds experiencing high and background levels of herbivory. In each watershed, four plots, each with three throughfall collectors, were established (n=24) collectors), and two bulk rainfall collectors were installed in areas without canopy cover. Throughfall and rainfall were collected from late June to early November 2015. Samples were analyzed for dissolved organic carbon (DOC), ammonium (NH4-N), and soluble reactive phosphorus (SRP). Over the sampling period, throughfall fluxes ranged 8.57 to 47.59 kg/ha for DOC, 0.004-0.011 kg/ha for NH4-N, and 007 - 0.29 kg/ha for SRP. Percent throughfall was slightly, but not significantly, higher in the high (48%) compared to the background watershed (42%). There were no differences in solute concentrations among the watersheds. Net throughfall fluxes, the sum of canopy uptake and leaching and dry/fog deposition, differed significantly for NH4-N by herbivory level and through time for NH4-N and DOC but not SRP. Over time, net NH4-N throughfall fluxes showed a clear transition from net uptake of NH4-N to net leaching of NH4-N in the high herbivory watershed. There was also a clearn NH4-N pulse in the high herbivory watershed after the first, but not subsequent, rainfall events. In this N-limited forest, altered throughfall N may affect soil nutrient cycling and downstream water quality.
Archaeological Proteomics: Method Development and Analysis of Protein-Ceramic Binding
The analysis of protein residues recovered from archaeological artifacts provides a unique opportunity to reveal new information about past societies. However, many scientists are currently unwilling to accept protein-based results due to problems in method development and a basic lack of agreement regarding the ability of proteins to bind to, and preserve within, artifacts such as pottery. In this paper, I address these challenges by conducting a two-phase experiment. First, I quantitatively evaluate the tendency of proteins to sorb to ceramic matrices by using total organic carbon analysis and spectrophotometric assays to analyze samples of experimentally cooked ceramic. I then test a series of solvent and physical parameters in order to develop an optimized method for extracting and preparing protein residues for identification via mass spectrometry. Results demonstrate that protein strongly sorbs to ceramic and is not easily removed, despite repeated washing, unless an appropriate extraction strategy is used. This has implications for the future of paleodietary, conservation ecology and forensic research in that it suggests the potential for recovery of aged or even ancient proteins from ceramic matrices.
The Impact of Chinese Privet (Ligustrum Sinense) on the Survival and Re-Establishment of Native Plants at the Dallas Floodway Extension
Invasive woody shrubs are a problem when they displace native species and threaten habitats, especially those that harbor rare or endangered species. They not only compete with native plants, but also alter habitat and food that many organisms depend upon. Invasive plants undergo a release from their specialist predators in the nonnative range, providing them advantages over native species. Because modes and pathways of how invasive species spread are not fully understood, predicting spread and implementing restoration ecological controls remain inexact. Due to the lack of comparative studies on woody shrubs, especially invasive privets, we understand very little about conditions affecting their invasiveness. A study was conducted near Dallas, Texas to determine if privet has allelopathic properties that influences growth of native plants. Soil nutrients and other analyses were made and compared between field plots supporting privet, plots in which privet has been removed, and plots where privet has not been observed. In some field plots, natives were planted under the three previously mentioned conditions, and their survival and condition were monitored to evaluate effects of privet on their establishment and growth. It was found that Chinese privet did hinder seed germination in red mulberry, soapberry and beautyberry and root formation in beautyberry cuttings. The soil in the sites were found to be normal for bottomland forests that endured two flooding events within one year.
A Spatial Decision Support System to Dynamically Compute and Map Neighborhood Indices
Neighborhoods are organic entities that are in a state of constant change and are driven by the specific context of the problem being investigated. The subsequent lack of consensus on a universal geographic definition for what constitutes a neighborhood can lead to biased interpretations of relationships between human activities and place. Further, while existing geographical information system software allows users to combine a range of geographic objects to generate regional units of analyses, their design does not explicitly assess how changing patterns, such as populations, impact the data expressed within them. This research develops an exploratory geographical information system framework that allows users to dynamically delineate neighborhoods based on user-specified characteristics. These include socioeconomic and similar measurements of neighborhood classification from information obtained from secondary data sources, including parcel data, land use/land cover information, and attribute data provided by the United States Postal Service. The proposed methodology creates custom geographies from readily available tract data obtained from various federal and state data repositories to produce indices. By allowing the user to dynamically weigh the combinations of variables used to define their neighborhood, this thesis introduces a solution to a common analytical problem in the discipline.
Hyperspectral and Multispectral Image Analysis for Vegetation Study in the Greenbelt Corridor near Denton, Texas
In this research, hyperspectral and multispectral images were utilized for vegetation studies in the greenbelt corridor near Denton. EO-1 Hyperion was the hyperspectral image and Landsat Thematic Mapper (TM) was the multispectral image used for this research. In the first part of the research, both the images were classified for land cover mapping (after necessary atmospheric correction and geometric registration) using supervised classification method with maximum likelihood algorithm and accuracy of the classification was also assessed for comparison. Hyperspectral image was preprocessed for classification through principal component analysis (PCA), segmented principal component analysis and minimum noise fraction (MNF) transform. Three different images were achieved after these pre-processing of the hyperspectral image. Therefore, a total of four images were classified and assessed the accuracy. In the second part, a more precise and improved land cover study was done on hyperspectral image using linear spectral unmixing method. Finally, several vegetation constituents like chlorophyll a, chlorophyll b, caroteoids were distinguished from the hyperspectral image using feature-oriented principal component analysis (FOPCA) method and which component dominates which type of land cover particularly vegetation were correlated.
Emergency Fire Response in Ghana: The Case of Fire Stations in Kumasi
Comprehensive emergency management and response is crucial for disaster prevention and health emergencies. However, in African countries with an abundance of natural disasters and a rising surge in cardiovascular and obstetric emergencies, little research exists on emergency response. This study examines the fire emergency response in Kumasi Metropolitan Assembly (KMA), Ghana's second largest city. We use Geographic Information Systems (GIS) tools including location -allocation modeling to evaluate the existing system of fire facilities, identify gaps in service, and suggest locations for new fire stations to maximize population coverage. Our results show that fire stations within KMA are poorly distributed and large portions of the metropolis are underserved, a situation that is partly responsible for the huge losses of lives and property during fire outbreaks.
Retail District Evolution: An Exploration of Retail Structure and Diversity, a Case Study in Denton, Texas
It is well established that national retail chains impact small, single location retail businesses in terms of revenue generation, retail structure, retail type diversity, and location. This study examines the retail structure and diversity of five retail districts in the City of Denton, Texas. The analysis focuses on one central business district (CBD), one traditional retail strip center (University Drive, also known as US HWY 380), one special retail district (Fry Street District), one traditional enclosed shopping mall and associated development (Golden Triangle Mall), and one power retail center (Denton Crossing). The empirical foundation for the investigation is a historical business database covering years 1997 to 2010, obtained from Info Group's Reference USA. This Reference USA database includes location, industry, and status (single versus chain location) information for each business. Retail diversity and evenness were measured for each of the five retail districts using the Simpson's Diversity Index and the Simpsons Measure of Evenness, leading to specification of the differences that exist in retail structure and diversity among the districts. Golden Triangle Mall and Denton Crossing were primarily chain location in composition while Fry Street District, the CBD, and University Drive were primarily single location in composition. Across all years, the single versus chain status of the local business communities did not substantially change within any of the districts. The Fry Street District exhibited the most change in diversity as well as the lowest overall diversity among the retail districts, followed by University Drive and Golden Triangle Mall. The CBD did not experience any major change in retail type diversity. However, all retail districts experienced major changes in retail evenness. Overall for the city, single location retail businesses accounted for the majority of all the retail businesses, however, chain locations employed more people. In total, these findings indicate that the …
Looking Outward from the Village: The Contingencies of Soil Moisture on the Prehistoric Farmed Landscape near Goodman Point Pueblo
Ancestral Pueblo communities of the central Mesa Verde region (CMVR) became increasingly reliant on agriculture for their subsistence needs during Basketmaker III (BMIII) through Terminal Pueblo III (TPIII) (AD 600–1300) periods. Researchers have been studying the Ancestral Pueblo people for over a century using a variety of methods to understand the relationships between climate, agriculture, population, and settlement patterns. While these methods and research have produced a well-developed cultural history of the region, studies at a smaller scale are still needed to understand the changes in farming behavior and the distribution of individual sites across the CMVR. Soil moisture is the limiting factor for crop growth in the semi-arid region of the Goodman Watershed in the CMVR. Thus, I constructed the soil moisture proxy model (SMPM) that is on a local scale and focuses on variables relevant to soil moisture – soil particle-size, soil depth, slope, and aspect. From the SMPM output, the areas of very high soil moisture are assumed to represent desirable farmland locations. I describe the relationship between very high soil moisture and site locations, then I infer the relevance of that relationship to settlement patterns and how those patterns changed over time (BMIII – TPIII). The results of the model and its application help to clarify how Ancestral Pueblo people changed as local farming communities. The results of this study indicates that farmers shifted away from use of preferred farmland during Terminal Pueblo III, which may have been caused by other cultural factors. The general outcome of this thesis is an improved understanding of human-environmental relationships on the local landscape in the CMVR.
Assessment of Transportation Emissions for Ferrous Scrap Exports from the United States: Activity-Based Maritime Emissions Model and Theoretical Inland Transportation Model.
Industrial ecology is a field of study that encourages the use of closed-loop material cycles to achieve sustainability. Loop closing requires the movement of materials over space, and has long been practiced in the iron and steel industry. Iron and steel (ferrous) scrap generated in the U.S. is increasingly exported to countries in Asia, lengthening the transportation distance associated with closing the loop on the iron and steel life cycle. In order to understand the environmental cost of transporting this commodity, an activity-based maritime transportation model and a theoretical in-land transportation model are used to estimate emissions generated. Results indicate that 10.4 mmt of total emissions were generated, and emissions increased by 136 percent from 2004 to 2009. Increases in the amount of emissions generated are due to increases in the amount of scrap exported and distance it is transported.
Identifying Cultural and Non-cultural Factors Affecting Litter Patterns in Hickory Creek, Texas
Plastic deposition in hydrological systems is a pervasive problem at all geographic scales from loci of pollution to global ocean circulation. Much attention has been devoted to plastic deposition in marine contexts, but little is known about inputs of plastics into local hydrological systems, such as streams. Any attempt to prevent plastic litter must confront people’s behaviors, so archaeological concepts are used to distinguish between various cultural inputs (e.g., littering) and non-cultural forces (e.g., stream transport) that affect litter patterns on the landscape. Litter surveys along Hickory Creek in Denton, TX, are used to assess these factors.
A Geoarchaeological Investigation of Site Formation in the Animas River Valley at Aztec Ruins National Monument, NM
This paper presents an investigation of sedimentary deposition, soil formation, and pedoturbation in the Animas River Valley to determine the provenience of archaeological deposits in an open field at Aztec Ruins National Monument, NM outside of the Greathouse complex. Four stratigraphic pedounits correlated with active fan deposition have been proposed for the lower terrace in the project area with only one of these units retaining strong potential for buried archaeological deposits from the Anasazi late Pueblo II/Pueblo III period. The distal fan on the lower terrace and the Animas River floodplain appear to show poor potential for archaeological deposits either due to shallow sediment overburden with historic disturbance or alluvial activity during or after occupation. Based on these findings, four other zones of similar fan development have been identified throughout the Animas Valley and are recommended for subsurface testing during future cultural resource investigations.
Lone Star Booster: The Life of Amon G. Carter
Abstract Though a very influential Texan during the first half of the twentieth century, Amon Carter has yet to receive a full scholarly treatment, a problem which this dissertation attempts to rectify by investigating the narrative of Carter’s life to see how and why he was able to rise from humble beginnings to become a powerful publisher who symbolized boosterish trends within Texas and the New South. Publisher of the Fort Worth Star-Telegram, philanthropist, oilman, and aviation supporter, Carter used his power and influence to become a leading booster of his city and region seamlessly making the transition from being a business progressive to New Deal supporter to an Eisenhower Democrat. His connections with corporations like American Airlines and General Motors helped bring aviation and industry to his region, and his ability to work with public and private entities helped inspire his failed attempt to make the Trinity River navigable up to Fort Worth. His own success at building the Star-Telegram into the largest circulating newspaper in Texas encouraged him to expand his media empire into radio and television, while the wealth he gained from his oil activities enabled him to form a philanthropic foundation that would provide support for Fort Worth’s medical, cultural, and educational needs for the future. Possessing a life marked by both success and failure, it is clear throughout this dissertation that Carter embodied the idea of the New South civic booster, a figure who at once promoted his goals for his city and region while understanding how this fit within the larger national context.
Developing a Wildlife Tracking Extension for ArcGIS
Wildlife tracking is an essential task to gain better understanding of the migration pattern and use of space of the wildlife. Advances in computer technology and global positioning systems (GPS) have lowered costs, reduced processing time, and improved accuracy for tracking wild animals. In this thesis, a wildlife tracking extension is developed for ArcGIS 9.x, which allows biologists and ecologists to effectively track, visualize and analyze the movement patterns of wild animals. The extension has four major components: (1) data import; (2) tracking; (3) spatial and temporal analysis; and (4) data export. Compared with existing software tools for wildlife tracking, the major features of the extension include: (1) wildlife tracking capabilities using a dynamic data layer supported by a file geodatabase with 1 TB storage limit; (2) spatial clustering of wildlife locations; (3) lacunarity analysis of one-dimensional individual animal trajectories and two-dimensional animal locations for better understanding of animal movement patterns; and (4) herds evolvement modeling and graphic representation. The application of the extension is demonstrated using simulated data, test data collected by a GPS collar, and a real dataset collected by ARGOS satellite telemetry for albatrosses in the Pacific Ocean.
Soil Characteristics Estimation and Its Application in Water Balance Dynamics
This thesis is a contribution to the work of the Texas Environmental Observatory (TEO), which provides environmental information from the Greenbelt Corridor (GBC) of the Elm Fork of the Trinity River. The motivation of this research is to analyze the short-term water dynamic of soil in response to the substantial rainfall events that occurred in North Texas in 2007. Data collected during that year by a TEO soil and weather station located at the GBC includes precipitation, and soil moisture levels at various depths. In addition to these field measurements there is soil texture data obtained from lab experiments. By comparing existing water dynamic models, water balance equations were selected for the study as they reflect the water movement of the soil without complicated interrelation between parameters. Estimations of water flow between soil layers, infiltration rate, runoff, evapotranspiration, water potential, hydraulic conductivity, and field capacity are all obtained by direct and indirect methods. The response of the soil at field scale to rainfall event is interpreted in form of flow and change of soil moisture at each layer. Additionally, the analysis demonstrates that the accuracy of soil characteristic measurement is the main factor that effect physical description. Suggestions for model improvement are proposed. With the implementation of similar measurements over a watershed area, this study would help the understanding of basin-scale rainfall-runoff modeling.
What's in Your Garden? Assessing the "Eco-friendliness" of Plant Choices of Denton, Texas Gardeners
Urbanization is seen as a threat to biodiversity within urban ecosystems, which are largely reliant on humans for their composition. Two types of extremes exist in the spectrum of urban domestic gardens; on one end, the typical urban garden which is planted by landscapers at the time the house is built and is generally left unchanged, and, at the other, a "wild" landscape planted entirely with native plants which provides habitat for native fauna and pollinators. This study assesses the plant choices made by members of organized gardening groups-the Denton County Master Gardeners (DCMG), the Elm Fork Master Naturalists (EFMN), the Trinity Forks Native Plant Society (TFNPS), and Keep Denton Beautiful (KDB)-and toward which extreme these choices put these gardens on the psectrum. TFNPS and EFMN both fall closer to the wild garden extreme, with TFNPS the closest to a "wild garden." DCMG was almost directly between the two extremes, but fell closer to the typical urban garden. By looking at how these groups manage their gardens, we begin to understand the ways in which gardeners can mitigate and soften the harsh changes between wild landscapes and urban environments. Collaboration between groups could have the potential to encourage more people to use native plants which provide habitat for native fauna and pollinators if those in the typical urban garden spectrum could find in the "wild" gardens of those on the opposite end of the spectrum.
Site Formation Processes and Bone Preservation Along the Trinity River Basin, North Central Texas
This thesis presents the results of geoarchaeological investigations of several archaeological sites along the Elm Fork of the Trinity River in north central Texas. Archaeological data recorded from mitigation excavations in Denton and Cooke counties were analyzed to understand the geologic impacts on faunal preservation resulting from site formation processes. The faunal assemblages are highly fragmented, even in settings known for good preservation. A combined approach using geoarchaeological and taphonomic techniques was implemented to examine how fragmentation, evidence of soil weathering, and differential preservation were impacted by differing geologic conditions throughout the river basin. Intrasite and intersite results of the sites show that a great deal of variability of faunal preservation is present at difference scales of analysis.
Spatial Patterns in Development Regulation: Tree Preservation Ordinances of the DFW Metropolitan Area
Land use regulations are typically established as a response to development activity. For effective growth management and habitat preservation, the opposite should occur. This study considers tree preservation ordinances of the Dallas-Fort Worth metropolitan area as a means of evaluating development regulation in a metropolitan context. It documents the impact urban cores have on regulations and policies throughout their region, demonstrating that the same urban-rural gradient used to describe physical components of our metropolitan areas also holds true in terms of policy formation. Although sophistication of land use regulation generally dissipates as one moves away from an urban core, native habitat is more pristine at the outer edges. To more effectively protect native habitat, regional preservation measures are recommended.
A Quantitative Assessment of Site Formation at the Dmanisi Archaeological Site, Republic of Georgia
The focus of this thesis was to gather and analyze micromorphological and petrographic data on soils at the archaeological site of Dmanisi in order to better understand the extent to which the deposition and alteration of the sediments has affected the preservation of artifacts and faunal remains. A major goal of this research was to test hypothesis related to why bone material is discovered in some strata and not in others. This research focuses on the application of micromorphology (supplemented with other methods) to the soils through the use of petrographic analysis of thin sections and scanning electron microscopy. These techniques complement previous field analyses by providing a quantitative assessment of individual strata through point counting and chemical mapping. The results of this research support the hypothesis that the sediments are predominantly mafic ashes, while showing that there is very little soil development in the strata. This suggests quick episodic burial in a relatively dry climate, confirming the hypothesis for a short time sequence in the strata. Additionally, differential weathering probably did not play a significant role in the differential abundance of bone remains among the strata at Dmanisi.
Examining the Role of Latitude and Differential Insolation in Asymmetrical Valley Development
Valley development through erosional processes typically tends to create symmetrical valleys. Over time, water cuts through the substrate to create valleys, gorges, and canyons for which the sides are the valley are evenly sloped. However, there are anomalies to this process. Asymmetrical valleys have been well-documented even in areas of uniform substrate or little tectonic uplift. One proposed explanation for the asymmetry of these valleys is differential insolation. This may lead to different microclimates from one slope to another which alter the rate and extent of erosion. Since the differences in received insolation vary with latitude (especially in streams that flow along an east/west axis), it follows that the degree of asymmetry should also vary with latitude if differential insolation is a primary driving factor in the development of these valleys. To evaluate if insolation plays a role in the development of asymmetrical valleys, this study examines variability in asymmetry across 447 valleys in nine study areas located at different latitudes. The degree of asymmetry for each valley was measured by using 30 meter resolution digital elevation models (DEMs) to determine the slope angle of each side of the valley. Asymmetry was measured by computing a ratio of the average slope angle for each side of the valley (larger value divided by smaller). If the resulting value is one, the valley is deemed symmetrical. As the value increases, the degree of asymmetry increases. This investigation found that contrary to expectations, valleys at lower latitudes tend to have a higher degree of asymmetry than those at higher latitudes, which suggests that differential insolation does not play a major role in the development of these valleys. Instead, this study found that high altitudes and low latitudes are more frequently associated with a higher degree of asymmetry. These unexpected findings open the door …
Finding Terroir in Southwest Iowa
Terroir combines the physical landscape of the vineyard with the grapevines and the methods and techniques used to produce wine from the grapes. This study used a GIS to identify the characteristics of the physical landscape in Pottawattamie, Mills, Montgomery, Fremont, and Page counties in southwestern Iowa. The components were combined in the GIS using a weighted linear index to identify areas suitable for vineyard development and to identify the general characteristics of the area. Vineyard owners were interviewed to help determine the weighting system to use in the GIS and to determine their perceptions of how the physical landscape impacts their vineyards, as well as to determine what grape varieties they plant in their vineyards and their decisions on making wine from these grapes. This information was collected to identify whether the vineyard owners had developed a sense of place for their vineyards and how this sense might aid them in the development of a terroir for their wines. The resulting perceptions about the individual wineries were then considered in conjunction with the results from the GIS modeling to understand how the physical landscape influences the concepts of sense of place and terroir in southwest Iowa. The physical landscape of southwest Iowa was fairly uniform, as were the grape varietals planted in the vineyards. This created a measure of similarity among the wineries, while individuality between wineries was then created by the wine-makers as they used different techniques to produce wine from the grapes. This allows each winery to develop a sense of place, yet be part of a larger sense of place that encompasses multiple wineries within the area.
Contribution of Hurricane Ike Storm Surge Sedimentation to Long-term Aggradation of Coastal Marshes in Southeastern Texas and Southwestern Louisiana
Coastal marshes and wetlands are vital natural resources that offer habitats for plants and animals, serve as ecological filtration for soil and water pollutants, and act as protection for coastlines. Fishing, both commercial and sport, has a large economic impact in the study area – the Gulf Coast between Galveston Bay, TX and Oak Grove, LA. The objective of this research was to determine the contribution of Hurricane Ike storm surge sedimentation to long-term marsh aggradation in Texas and Louisiana coastal marshes. The research hypothesized that Hurricane Ike’s storm surge deposit would be equal to decades and possibly even a century’s worth of the average annual non-storm sedimentation. A quantitative field study was performed. The storm surge deposit was examined in a series of 15 transects covering approximately 180 km east of Hurricane Ike’s landfall. Nine of the 15 transects were re-surveyed a year after the initial measurement to assess preservation of the deposit. The results demonstrate that Hurricane Ike contributed between 10 to 135 years’ worth of sediment to coastal marshes along the coasts of Texas and Louisiana, and the sediment deposits have been preserved for over two years.
Testing New Measures of Age Independent Body Size in White-Tailed Deer (Odocoileus virginianus)
The four elements of the lower hind foot (calcaneus, metatarsal, naviculo-cuboid, and tibia) were tested for use as age-independent proxies of body size in white-tailed deer using known aged specimens from Ft. Hood Texas. Statistical analysis indicates that the calcaneum and the tibia are good proxies of age-independent body size in white-tailed deer. In addition to expanding the list of elements that can be used for studies of age-independent body size, these elements can also be used to age faunal remains to an ordinal scale of juveniles and adults. This is useful for research regarding prehistoric prey populations; as a single element can be used to determine prey body size and age simultaneously, which are the two variables used to assess changes in human subsistence practices via the archaeological remains of their prey.
Estimating Buruli Ulcer Prevalence in Southwestern Ghana
Mycobacterium ulcerans is sweeping across sub-Saharan Africa, but little is known about the mode of transmission and its natural reservoirs. Since the only effective treatment is excision of the infection and surrounding tissue, early diagnosis and treatment is the only way to reduce the havoc associated with Buruli ulcer. Using data from a national case search survey conducted in Ghana during 2000 and suspected risk factors this study tests the hypothesized factors and probes the challenges of developing a spatial epidemiological regression model to explain Buruli ulcer prevalence in the southwestern region of Ghana representing 42 districts. Results suggest that prevalence is directly related to the degree of land cover classified as soil, elevation differential, and percent rural population of the area.
Influence of the Choice of Disease Mapping Method on Population Characteristics in Areas of High Disease Burdens
Disease maps are powerful tools for depicting spatial variations in disease risk and its underlying drivers. However, producing effective disease maps requires careful consideration of the statistical and spatial properties of the disease data. In fact, the choice of mapping method influences the resulting spatial pattern of the disease, as well as the understanding of its underlying population characteristics. New developments in mapping methods and software in addition to continuing improvements in data quality and quantity are requiring map-makers to make a multitude of decisions before a map of disease burdens can be created. The impact of such decisions on a map, including the choice of appropriate mapping method, not been addressed adequately in the literature. This research demonstrates how choice of mapping method and associated parameters influence the spatial pattern of disease. We use four different disease-mapping methods – unsmoothed choropleth maps, smoothed choropleth maps produced using the headbanging method, smoothed kernel density maps, and smoothed choropleth maps produced using spatial empirical Bayes methods and 5-years of zip code level HIV incidence (2007- 2011) data from Dallas and Tarrant Counties, Texas. For each map, the leading population characteristics and their relative importance with regards to HIV incidence is identified using a regression analysis of a CDC recommended list of socioeconomic determinants of HIV. Our results show that the choice of mapping method leads to different conclusions regarding the associations between HIV disease burden and the underlying demographic and socioeconomic characteristics. Thus, the choice of mapping method influences the patterns of disease we see or fail to see. Accurate depiction of areas of high disease burden is important for developing and targeting appropriate public health interventions.
A Spatial-Temporal Analysis of Retail Location and Clustering: A Case Study of Port Huron, MI
Retail geography is a field of study that is growing in significance and importance within the academic, business, economic, and governmental realms. This study's main focus is on the changing retail environment with regards to business location and function within a small Midwestern city. The research focuses on Port Huron, Michigan because of the growth and shift of the retail community within the city over the past twenty years. The study specifically examines the changing influence and roles of Port Huron's central business district and of Birchwood Mall a retail development opened on the urban area's north end in 1990. The study uses the chi-squared, ANOVA, and cross tabulation statistical tests to analyze the changing geography of retail functions in the city. These statistics are used along with relative entropy equations to distinguish areas of high diversification, changing area functions, and common locations for multiple retail types.
Installation and Manufacturing of Photovoltaics: an Assessment Using California and New York
Renewable energy studies are becoming increasingly important as world energy demand rises and current energy sources are increasingly questioned. Solar photovoltaics (PV) are the focus of this study as a renewable industry still in its infancy. This research examines the geography of solar panel installation and manufacturing from 2007 to 2010 in California and New York. California is the larger of the two markets and has implemented more policy support; programs that appear to have increased the pace of installations, reduce the size of the subsidy, and help lower total costs. Similar trends are observable in New York. US based companies are still making solar panels, but foreign competitors, most notably from China and Mexico, are capturing an increasing share of the market.
The Descriptive Paleontology and Applied Ichthyoarchaeology of the Ponsipa Fauna
The archaeology of the Northern Rio Grande region of New Mexico has recently received an increased amount scholarly attention. In particular, understanding past trends in demographics, agricultural productivity, violence, and social networks have been primary goals of archaeological research. Understanding patterns in animal exploitation has, however, received far less attention due to a small yet growing regional zooarchaeological database. Through the identification of animal remains from a site called Ponsipa (occupied ca. A.D. 1300 to 1600), this thesis adds one large dataset to this growing database. In addition, this thesis expands on the pre-impoundment distribution of an endangered native freshwater fish species in the state of New Mexico called the blue sucker (Cycleptus elongatus). The blue sucker is a unique fish that is currently experiencing range reduction across all of its known North American distribution due to anthropogenic habitat fragmentation and degradation. Skeletal remains that were identified from Ponsipa represent the farthest known northern record of its occurrence in the state of New Mexico and highlight the extent of range restriction of the species in the area. The data concerning the historical biogeography of the blue sucker from Ponsipa have implications for the effective conservation and restoration of blue sucker located in the Rio Grande Basin.
Spatial Analysis of Teen Births in North Central Texas
The United States has the highest teen birth rate among western industrialized countries and the highest levels of pregnancy among adolescents (Alan Guttmacher Institute, 1994). While the rate of teen births is high throughout the country, considerable variations exist between and within regions. Texas is one of the 5 leading states with the highest teen birth rates to mothers less than 18 years of age. This research provides a detailed analysis of births to mothers aged between 10 and 19 years in North Central Texas counties. Due to the modifiable area unit problem and to provide a finer geographical scale of analysis, teen births in Dallas County zip codes were examined as a special case study. Statistical and Geographic Information System (GIS) analysis reveal that race/ethnicity, education and income are significant factors in teen births in the region. Single parent households and receipt of public assistance were not statistically significant. Suggestions for reducing vulnerability to teen births are presented.
Geography of Tuberculosis in the Greater Accra Region of Ghana
In Ghana, spatial patterns of TB vary for different regions and variations may occur within the same region. This study examines TB distribution in the Greater Accra Region of Ghana using Geographic Information Systems (GIS). Behavioral, cultural and economic variables associated with TB morbidity are examined. From January 1998 to June 1999, data obtained from the Ghana Ministry of Health revealed that, men had a higher TB rate than women, TB was common among the age groups 20-29 and 30-39, and the average TB rate of 67.7 per 100, 000 population in the Greater Accra Region was higher than the national average (58.6 per 100,000 population). Using the human ecology model, this study attempts to explain the spatial distribution of the disease.
Structure, Composition, and Regeneration of Cross Timbers Forest Fragments in Different Land Use Contexts
Throughout its current range, the Cross Timbers forest ecosystem is vulnerable to land-use change. In this study, we examined the surrounding land use matrix on the vegetation structure, composition and regeneration of six Cross Timbers forest fragments in Denton County, Texas (north of the Dallas-Fort Worth metroplex). Two fragments adjacent to agricultural land, two to residential neighborhoods, and two formally protected forest sites were selected. In summer 2015, five 100 m2 plots were randomly established in each fragment at least 200 meters from the edge. In each plot, all live and dead trees ≥ 3 cm diameter were identified and their height and diameter at breast height (DBH at 1.3 m aboveground) measured. Evidence of dumping (presence of trash) was recorded as an index of human frequentation. Differences in vegetation structure among the forest fragments were found. Most notably, fragments adjacent to agriculture contained 25% to 50% fewer trees per hectare than all other sites (Kruskal-Wallis, p < 0.02), especially trees <10 cm DBH. However, residential fragments had fewer trees that were ≥15 cm DBH compared to the other fragments, indicating that these are the youngest of the forest patches surveyed. Trash was observed in 60% of plots surveyed at residential forest sites, showing high levels of human frequentation compared to the protected and agricultural forest sites. Agricultural sites contained the lowest number of recorded tree species and were most similar to each other, sharing 91% of species. These findings indicate that surrounding land use affects forest structure and composition, consequently affecting valuable ecosystem services including wildlife habitat, aesthetics and recreation.
Integrating GIS with Benthic Metrics: Calibrating a Biotic Index to Effectively Discriminate Stream Impacts in Urban Areas of the Blackland Prairie Eco-Region
Rapid Bioassessment Protocols integrate a suite of community, population, and functional metrics, determined from the collection of benthic macroinvertebrates or fish, into a single assessment. This study was conducted in Dallas County Texas, an area located in the blackland prairie eco-region that is semi-arid and densely populated. The objectives of this research were to identify reference streams and propose a set of metrics that are best able to discriminate between differences in community structure due to natural variability from those caused by changes in water quality due to watershed impacts. Using geographic information systems, a total of nine watersheds, each representing a different mix of land uses, were chosen for evaluation. A total of 30 metrics commonly used in RBP protocols were calculated. Efficacy of these metrics to distinguish change was determined using several statistical techniques. Ten metrics were used to classify study area watersheds according to stream quality. Many trends, such as taxa presence along habitat quality gradients, were observed. These gradients coincided with expected responses of stream communities to landscape and habitat variables.
The Geography of Maternal Mortality in Nigeria
Maternal mortality is the leading cause of death among women in Nigeria, especially women aged between 15 and 19 years. This research examines the geography of maternal mortality in Nigeria and the role of cultural and religious practices, socio-economic inequalities, urbanization, access to pre and postnatal care in explaining the spatial pattern. State-level data on maternal mortality rates and predictor variables are presented. Access to healthcare, place of residence and religion explains over 74 percent of the spatial pattern of maternal mortality in Nigeria, especially in the predominantly Muslim region of northern Nigeria where poverty, early marriage and childbirth are at its highest, making them a more vulnerable population. Targeting vulnerable populations in policy-making procedures may be an important strategy for reducing maternal mortality, which would also be more successful if other socio-economic issues such as poverty, religious and health care issues are promptly addressed as well.
The Influence of Local Forage Variability on White-tailed Deer (Odocoileus virginianus) Body Size at Fort Hood, Texas
Nutritional quality and availability is thought to regulate geographic patterns of variability in animal body size due to phenotypic plasticity. The purpose of this study is to determine how vegetation quality, abundance and population density influence white-tailed deer (Odocoileus virginianus) body size on a subregional spatial scale at Fort Hood, Texas. Harvest and census records are used to test the hypothesis that white-tailed deer exhibit phenotypic plasticity (e.g. larger body size) in response to differences in vegetation quality and availability. Results from these analyses suggest that forage quality and abundance alone is not a main driver of white-tailed deer body size. Analysis of deer population density (generally) resulted in an inverse relationship with body size. Areas with high quality forage and low population density support larger deer while areas with low quality forage and high density support smaller than average deer. The few exceptions occur in areas exhibiting poor quality forage and low population density or high forage quality and high density. Results from this study suggest that continued overcrowding of deer within isolated areas may eventually lead to efficiency phenotypic conditions producing smaller sized deer. These results could prove useful in interpreting deer population responses to harvest management. For successful local management of deer, studies examining the combined influence of habitat variables (such as forage quality, abundance and population density) on deer health offer managers valuable information needed to establish annual harvest goals and understand deer-habitat relationships relative to carrying capacity.
Assessing Rainfall Interception by Urban Tree Canopies in Denton, Texas
Rainfall interception is one mechanism by which tree canopies can reduce surface runoff in urban areas. The objectives of this research were to: 1) quantify rainfall interception by urban tree canopies, and 2) determine the influence of vegetation and microenvironmental factors on rainfall interception rates. In the city of Denton, Texas, 30 mature post oak (Quercus stellata) and blackjack oak (Quercus marilandica) trees were selected for study. Trees were assigned to one of three categories: clusters of trees on greenspace (CG), isolated trees on greenspace (IG), and isolated trees surrounded by pavement (IP). Throughfall (the volume of water that travels through the canopy and reaches the soil surface) collectors were placed beneath these trees and rainfall collectors were placed in nearby open areas. Throughfall and rainfall were collected daily from 19 March to 4 July. Interception was calculated as the difference between throughfall and gross rainfall. Over the study period, there were 27 days with measurable rainfall; daily rainfall ranged from 1-51 mm. Over the sampling period, rainfall interception for individual trees ranged from -10% to 49%, indicating high spatial variability in interception. Percent interception was highest for the CG treatment (22.7 ± 3.8 SE), intermediate for IG (27.4 ± 2.3 SE), and lowest for IP (9.1 ± 4.9 SE). Factors like wind exposure, wind-driven rain and overall tree health may help explain this variability. This research will contribute to our knowledge of hydrological fluxes in urban areas and the role of urban green infrastructure in stormwater runoff mitigation.
Evaluating Sea-Level Rise Hazards on Coastal Archaeological Sites, Trinity Bay, Texas
This study uses the predictive modeling program Sea-Levels Affecting Marshes Model (SLAMM) to evaluate sea-level rise hazards, such as erosion and inundation, on coastal archaeological sites with a vertical rise of sea level of .98 meters from 2006 to 2100. In total 177 archaeological site locations were collected and georeferenced over GIS outputs maps of wetlands, erosion presence, surface elevation, and accretion. Wetlands data can provide useful information about characteristics of the wetland classes, which make a difference in the ability for coastal archaeological sites to combat sea level rise. Additionally, the study evaluated predicted erosion of archaeological sites by presence or absence of active erosion on a cell-by-cell basis. Elevation map outputs relative to mean tide level allowed for a calculation of individual archaeological site datums to use NOAA tidal databases to identify the potential for their inundation. Accretion maps acquired from the SLAMM run determined the potential for the archaeological site locations to combat rising sea levels and potentially provide protection from wave effects. Results show that the most significant hazard predicted to affect coastal archaeological sites is inundation. Approximately 54% of the total archaeological sites are predicted to be inundated at least half the time by 2100. The hazard of erosion, meanwhile, is expected to affect 33% of all archaeological sites by the end of the century. Although difficult to predict, the study assumes that accretion will not be able to keep pace with sea-level rise. Such findings of hazards prove that SLAMM is a useful tool for predicting potential effects of sea-level rise on coastal archaeological sites. With its ability to customize and as it is complementary, it provides itself not only an economical choice but also one that is adaptable to many scenarios.
Resource Intensification of Small Game Use at Goodman Point, Southwestern Colorado
This analysis of faunal remains from eleven archaeological sites in the northern San Juan region, extensively occupied by the Ancestral Pueblo people until they leave the region by AD 1300, explores the effects of resource intensification of small wild and domestic resources leading up to this regional depopulation. By examining multiple lines of evidence, in addition to faunal abundance, causal factors are identified to address changes in abundances through time. In particular, age- and sex-based mortality are examined for lagomorphs (jackrabbits and cottontails) and domesticated turkey, respectively, to test hypotheses generated using the prey and patch choice models. Analyses of these resources follow a systematic paleontology which provides explicit identifications made of five sites from a large study area, Goodman Point Pueblo Unit. These data are integrated with those from large village sites from the encompassing central Mesa Verde region. The results of both analyses help clarify why the Ancestral Pueblo people left southwestern Colorado. During the final twenty-year occupation period, the results of this study support a shift from reliance on turkey husbandry to intense exploitation of locally available garden resources (i.e. cottontails).
Using Geographic Information Systems for the Functional Assessment of Texas Coastal Prairie Freshwater Wetlands Around Galveston Bay
The objective of this study was to deploy a conceptual framework developed by M. Forbes using a geographic information system (GIS) approach to assess the functionality of wetlands in the Galveston Bay Area of Texas. This study utilized geospatial datasets which included National Wetland Inventory maps (NWI), LiDAR data, National Agriculture Imagery Program (NAIP) imagery and USGS National Land Cover data to assess the capacity of wetlands to store surface water and remove pollutants, including nitrogen, phosphorus, heavy metals, and organic compounds. The use of LiDAR to characterize the hydrogeomorphic characteristics of wetlands is a key contribution of this study to the science of wetland functional assessment. LiDAR data was used to estimate volumes for the 7,370 wetlands and delineate catchments for over 4,000 wetlands, located outside the 100-yr floodplain, within a 2,075 square mile area around Galveston Bay. Results from this study suggest that coastal prairie freshwater wetlands typically have a moderate capacity to store surface water from precipitation events, remove ammonium, and retain phosphorus and heavy metals and tend to have a high capacity for removing nitrate and retainremove organic compounds. The results serve as a valuable survey instrument for increasing the understanding of coastal prairie freshwater wetlands and support a cumulative estimate of the water quality and water storage functions on a regional scale.
Rail Transit and Its Influence on Land Use: A Dallas Case Study
Mass transit investments continue to be utilized in many cities as means of dealing with various transportation issues. In Dallas Texas, light rail transit was developed with the hopes of encouraging compact and orderly growth. This research uses the DART system as a case study in examining transportation/land use relationships in Dallas. As such, this thesis reviews past research that examined transit systems impacts on urban areas, analyzes historical changes in land use pattern development around the existing twenty stations of the DART light rail starter system, and summarizes the progression of land use trends in the transit corridor as they relate to DART impacts. Results of this study suggest that DART's light rail system has been an effective tool used in achieving the transportation and land use goals for the region. Finally, recommendations are presented with respect to what can be expected for future light rail development in Dallas.
A Multiscalar Analysis of Buruli Ulcer in Ghana: Environmental and Behavioral Factors in Disease Prevalence
Buruli ulcer (BU), an infectious disease caused by Mycobacterium ulcerans, is the third most common mycobacterial disease after leprosy and tuberculosis and a WHO-defined neglected tropical disease. Despite years of research, the mode of transmission of BU remains unknown. This master’s thesis provides an integrated spatial analysis of disease dynamics in Ghana, West Africa, an area of comparatively high BU incidence. Within a case/matched control study design, environmental factors associated with BU infection and spatial behaviors are investigated to uncover possible links between individual daily activity spaces and terrains of risk across disturbed landscapes. This research relies upon archival and field-collected data and analyses conducted with geographical information systems (GIS).
FACET Simulation in the Imataca Forest Reserve, Venezuela: Permanent Plot Data and Spatial Analysis
Tree diameter data from 29 years of observations in six permanent plots was used to calculate the growth rate parameter of the FACET gap model for 39 species in the Imataca forests in Venezuela. The compound topographic index was used as a measure of differential soil water conditions and was calculated using geographic information systems. Growth rate values and topographic conditions typical of hill and valley were input to FACET to simulate dynamics at the species level and by ecological and functional groups. Species shade-tolerance led to expected successional patterns. Drought-tolerant/saturation-intolerant species grew in the hills whereas drought-intolerant/saturation-tolerant species occurred in the valleys. The results help to understand forest composition in the future and provide guidance to forest management practices.
Importance and Spatial Distribution of Phytophthora Ramorum Host Species in a Coast Redwood Forest
Phytophthora ramorum, an exotic forest pathogen known as ‘sudden oak death’ (SOD), has received considerable attention in recent years because of its effects on vegetation structure, composition, and fire disturbance regimes in western U.S. coastal forests. This research examines differences in the importance (e.g., density, dominance, and frequency) and distribution of five host species of P. ramorum–– Umbellularia californica (California bay laurel), Quercus agrifolia (coast live oak), Pseudotsuga menziesii (Douglas fir), Sequoia sempervirens (Coast redwood), and Arbutus menziesii (Madrone)––in Soquel, California. A stratified random sampling design was used to select 66 plots surrounding a managed forest edge in Soquel Demonstration State Forest. Vegetation measurements were conducted in summer 2013. In each plot, all trees ≥3 cm diameter at breast height (DBH) were identified to species, counted, and DBH, height, and canopy position measured. Leaf area index (LAI) of bay laurel was measured to quantify the amount of leaves available for pathogen dispersal with a LiCOR 2200 Plant Canopy Analyzer. In addition, morning (9:00 am) and afternoon (1:00 pm) photosynthetically active radiation (PAR) were quantified using a quantum light sensor. This paper examines the influence of environmental variables, including distance to edge, aspect, slope, and light availability on host species spatial patterns in Soquel, CA. Studying P. ramorum host pattern and importance among managed forest edges is critical for determining hotspots most susceptible to infection and spread, thus relevant for implementing control measures.
Geologic and Lithic Analysis of the Red River Cache
The Red River Cache is an assemblage of 33 bifaces, found in Cooke County, along Cache Creek, a tributary to the Red River. Also found with the cache was a hearth which yielded charcoal for AMS dating which returned an age of 2770- 2710 Cal YBP placing the cache in the Late Archaic. The geologic investigation of Cache Creek established 3 Holocene allostratigraphic units that provide information depositional environments adjacent to the Red River. Lithic analysis explored the production of bifaces during the Late Archaic and compared the cache to regional records. Using both geologic and lithic analysis this thesis investigates the temporal and cultural context of the cache using a geoarchaeological approach.
Reconstructing Identity with Urban Community Agriculture: How Refugees Confront Displacement, Food Insecurity, and Othering through Community Farming
Ethnic and religious conflict, and the deepening of capitalism have led to global diaspora at unprecedented levels. The United Nations High Commissioner for Refugees reported that as of 2015, 1 in every 122 persons worldwide were either a refugee, internally displaced, or seeking asylum. The U.S. currently admits the largest number of refugees worldwide. However, policies fail to reflect the multitude of elements that constitute successful resettlement. Moreover, many refugees come from farming backgrounds and are forced to migrate to a landless urban environment, where their skill sets may not be utilized and farm land is not available. I argue that existing resettlement processes are embedded in logics and practices that alienate humans from nature and from each other through competition, isolation, and placeless environments. Through an exploration in concepts of urban agriculture, place-making, identity, and otherness, and illuminating the experiences of resettled refugees involved in a community gardening project in Fort Worth, Texas, show how the urban refugee garden provides the individual a space to narrate an identity, and to resist industrial agriculture and labor outside their industry. Exploring best practices in resettlement should be a priority to governments, politicians, and communities involved in the process and highlight the reasons to advocate these types of resettlement alternatives.
Effects of Vegetation Structure and Canopy Exposure on Small-scale Variation in Atmospheric Deposition Inputs to a Mixed Conifer Forest in California
Data on rates of atmospheric deposition is limited in many montane ecosystems, where high spatial variability in meteorological, topographic, and vegetation factors contributes to elevated atmospheric inputs and to the creation of deposition hotspots. Addressing the ecological consequences of increasing deposition in these areas will require a better understanding of surface controls influencing atmospheric deposition rates at both large and small-scales. The overarching objective of this thesis research was to understand the influence of vegetation structure and canopy exposure on small-scale patterns of atmospheric sulfate, nitrate, and chloride deposition inputs to a conifer forest in the Santa Cruz Mountains, California. Throughfall ion fluxes (i.e., ions delivered in water that pass from the forest canopy to the forest floor), bulk deposition (i.e., primarily wet deposition), and rainfall data were collected during the rainy period from October 2012 to May 2013. Throughfall SO42-, Cl-, and NO3- fluxes were measured beneath eight clusters of Douglas fir (Pseudotsuga menziesii) trees (three trees per cluster) differing in tree size (i.e., diameter at breast height; DBH) and canopy exposure. In each cluster, a throughfall collector was placed 1-meter from the bole of an individual tree, for a total of 24 individual collectors. The position of each throughfall collector was recorded with a Trimble® GPS. In addition, tree height, tree diameter, and leaf area index, were measured for all trees. LiDAR data were obtained from GeoEarthScope’s Northern California Airborne LiDAR project and used to model the elevation (DEM), canopy surface height (DSM), tree height (CHM), slope, and curvature of the canopy surface across the entire study area. Over the rainy season, total throughfall flux of SO42--S, a conservative tracer of total deposition (wet + dry + fog), to Douglas fir clusters ranged from 1.44 - 3.84 kg S ha-1 wet season-1, while dry and fog deposition ranged …
Assessment of Sediment Runoff from Natural Gas Well Development Sites.
Storm water sediment runoff from disturbed landscapes has the potential to impair aquatic environments. Small construction sites of 1-5 acres in the United States are currently regulated by the United States Environmental Protection Agency to minimize storm water runoff damages to the environment. Gas well construction sites are similar to other construction sites in how the landscape is altered, but are not similarly regulated. This study identified sediment runoff from gas well development sites by collecting it in traps and weirs, and by measuring sediment debris lobes. Sediment primarily consisted of silt and clay sized particles. Sediments from two gas well sites formed five debris lobes that ranged in size from 325 to 3,290 square feet. Sediment loadings estimated from the debris lobes averaged 57.1 tons per year/acre. Future studies should focus on further quantification of sediment movement off of gas well sites and identify effective erosion control methods.
Spatial Analysis of Hiv/aids Survival in Dallas and Harris Counties, Texas
More Texans are living with HIV infection than ever before. in fact, there has been a 6% increase annually, since 2002. This trend is not a result of increased HIV/AIDS incidence, but rather improving life expectancy of those living with HIV. Due to significant advances in HIV/AIDS testing, prevention, and treatment, individuals with HIV are living longer than ever before. However, throughout the state, the life expectancy of a person infected with HIV/AIDS varies spatially. This study investigates and attempts to explain the spatial distribution of HIV/AIDS survival rates by examining neighborhood socioeconomic characteristics. the results suggest that, contrary to expectation, the lowest survival rates occur, not in extreme poverty areas, but rather in moderate SES areas. Too rich to qualify for free treatments, but not rich enough to afford purchasing such treatments, the middle income living with HIV infection are caught between the cracks. the results provide important input for targeting public health interventions to improve HIV/AIDS survival.
Geography of HIV Infection Among Adults Aged 50 Years and Older in Texas From 1999-2009
Twenty four percent of all HIV infections in the United States occur among adults aged 50 and older (mature adults), yet little is understood of the dynamics of HIV infection among this group in Texas. Data from 1999 to 2009 examined the relationship between HIV spatial and temporal patterns affecting socio-economic and demographic variables including poverty, gender, race/ethnicity and mode of exposure. Results revealed highest HIV infection rates among White homosexual men, Black males engaged in IV-drug use, Black female heterosexuals and minorities in poverty. Concentrations of HIV infection among mature adults were located primarily in urban centers of Houston and Dallas and indicated increasing HIV infection rates from 1999 to 2009. These results will assist future allocation of resources by zip code in urban areas for this understudied population.
Archaeological Site Vulnerability Modeling for Cultural Resources Management Based on Historic Aerial Photogrammetry and LiDAR
GIS has been utilized in cultural resources management for decades, yet its application has been largely isolated to predicting the occurrence of archaeological sites. Federal and State agencies are required to protect archaeological sites that are discovered on their lands, but their resources and personnel are very limited. A new methodology is evaluated that uses modern light detection and ranging (LiDAR) and historic aerial photogrammetry to create digital terrain models (DTMs) capable of identifying sites that are most at risk of damage from changes in terrain. Results revealed that photogrammetric modeling of historic aerial imagery, with limitations, can be a useful decision making tool for cultural resources managers to prioritize conservation and monitoring efforts. An attempt to identify key environmental factors that would be indicative of future topographic changes did not reveal conclusive results. However, the methodology proposed has the potential to add an affordable temporal dimension to future digital terrain modeling and land management. Furthermore, the methods have global applicability because they can be utilized in any region with an arid environment.
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