Browsing by Author "Ashby, Jeffrey L."

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    Exposure Characterization of Haloacetic Acids in Humans for Exposure and Risk Assessment Applications: An Exploratory Study
    (MDPI, 2019-01) Parvez, Shahid; Ashby, Jeffrey L.; Kimura, Susana Y.; Richardson, Susan D.; Environmental Health Science, School of Public Health
    Disinfected water is the major source of haloacetic acids (HAAs) in humans, but their inter- and intra-individual variability for exposure and risk assessment applications is under-researched. Thus, we measured HAAs in cross-sectional and longitudinal urine and water specimens from 17 individuals. Five regulated HAAs—mono-, di-, and trichloroacetic acid (MCAA, DCAA, and TCAA) and mono- and dibromoacetic acid (MBAA and DBAA)—and one unregulated HAA—bromochloroacetic acid (BCAA)—were measured. Urinary DCAA, MBAA, DBAA, and BCAA levels were always below the limits of detection (LOD). Measured levels and interindividual variability of urinary MCAA were higher than urinary TCAA. Longitudinal urinary specimens showed MCAA levels peaked in after-shower specimens, while TCAA levels remain unchanged. Correlation between urinary MCAA and TCAA was moderate but statistically significant. The prevalence of MCAA and TCAA in urine suggest they can be considered as biomarkers of HAA. Peak urinary MCAA in post-shower specimens suggest MCAA captures short-term exposure via dermal and/or inhalation, while urinary TCAA captures long-term exposure via ingestion. However, further research is warranted in a large pool of participants to test the reliability of MCAA as exposure biomarker.
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    Impact of the Proposed I-69 Corridor on Bobcat (Felis rufus) Habitat in Southwestern Indiana
    (Office of the Vice Chancellor for Research, 2013-04-05) Ashby, Jeffrey L.
    “Habitat loss is known to be the main cause of the current global decline in biodiversity, and roads are thought to affect the persistence of many species by restricting movement between habitat patches” (Eigenbrod, Hecnar et al. 2008). This research looks at the impact of the I-69 corridor being built in Southwestern Indiana on Bobcat habitat (Felis rufus) identified through the use of remote sensing and GIS. Bobcats are solitary animals that require steep, forested areas with plenty of cover for both themselves and the small mammals they prey upon. Identifying where Bobcats are likely is the first step in knowing the impact on their diversity in Southwestern Indiana. In this research, we used the 2012 National Agriculture Imagery Program (NAIP) imagery for each of the 47 counties in this study, along with the 2005 IndianaMap Elevation Model (DEM) data, both obtained from the Indiana Geospatial Portal (gis.iu.edu). These were combined with the cities and town, interstate, and highway shapefiles from the IndianaMap website (indianamap.org), and then classified and assigned suitability values to highlight high, medium, and low probability locations for Bobcats within the study area. The I-69 corridor shapefile was then added and the reduction in habitat calculated to show the impact the corridor will have on existing Bobcat habitat. The methods used in this research project can be used by State and other agencies to evaluate the impact on not only Bobcat habitat, but adapted to other species as well.
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    Niche Modeling of Dengue Fever Using Remotely Sensed Environmental Factors and BRT
    (OJPHI, 2018) Ashby, Jeffrey L.; Moreno-Madriñán, Max J.; Health Policy and Management, School of Public Health
    In this paper we used Boosted Regression Tree analysis coupled with environmental factors gathered from satellite data, such as temperature, elevation, and precipitation, to model the niche of Dengue Fever (DF) in Colombia.
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    Spatial Distribution of Children with an ASD Enrolled in Indiana Public Schools Compared to Quality-of-Life Indicators
    (Office of the Vice Chancellor for Research, 2014-04-11) Ashby, Jeffrey L.
    Autism Spectrum Disorder (ASD) is currently the fastest-growing developmental disability in the United States with the current prevalence rate of 1 in 88 as reported by the Centers for Disease Control and Prevention (CDC) Autism and Developmental Disabilities Monitoring (ADDM) Network. This increase has particularly impacted schools, since according to the Individuals with Disabilities Education Improvement Act [IDEA], these students must be served in the least restrictive environments that may range from special to inclusive classrooms. As such, it is important to assess the situation across the state of Indiana to better understand the areas of need and the distribution of this special population. This poster will take a spatially descriptive and quantitative approach to where and how ASDs are distributed across the state of Indiana using tools similar to those used by epidemiologist, such as crude rates and Bayesian modeling. Data were provided by the Indiana Department of Education and included a list of all public school districts in the state and the number in each district diagnosed with an ASD. A set of ten U.S. Census variables were identified from the literature and used to create a quality-of-life indicator to compare with the results of the spatial analysis. Based on the analysis, we can conclude that while autism in Indiana schoolchildren appears to be evenly distributed across the state, the more rural areas are at risk for services and should be made a priority for resources provided by the state and those NGO’s that specialize in helping those parents and families with children with ASDs.