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Minerals And Macrophages: Testing The Silica Paradigm And Soil Toxicity In The Etiology Of Podoconiosis, Jamey N. Cooper

Loma Linda University Electronic Theses, Dissertations & Projects

Certain earth materials, most famously silica and asbestos, are harmful to humans and can induce systemic disease. Podoconiosis is a disease affecting a large population in Ethiopia. Existing etiological models invoke a link to the composition of specific local volcanic soils. Silica and aluminum-containing minerals are hypothesized to induce inflammation, leading to obstructions within the lymphatic system of the legs. Multivariate analyses of bedrock geochemistry from regions associated with podoconiosis suggest an association with rocks composed of high levels of alkalines and silica. Soil samples from 29 towns with and without cases of podoconiosis were collected from across Ethiopia. Geological …

Widespread Infilling Of Tidal Channels And Navigable Waterways In The Human-Modified Tidal Deltaplain Of Southwest Bangladesh, C. Wilson, S. Goodbred, C. Small, J. Gilligan, S. Sams, B. Mallick, R. Hale

OES Faculty Publications

Since the 1960s, ~5000 km² of tidal deltaplain in southwest Bangladesh has been embanked and converted to densely inhabited, agricultural islands (i.e., polders). This landscape is juxtaposed to the adjacent Sundarbans, a pristine mangrove forest, both well connected by a dense network of tidal channels that effectively convey water and sediment throughout the region. The extensive embanking in poldered areas, however, has greatly reduced the tidal prism (i.e., volume of water) transported through local channels. We reveal that >600 km of these major waterways have infilled in recent decades, converting to land through enhanced sedimentation and the direct blocking …

Use Of Environmental Isotope Tracer And Gis Techniques To Estimate Basin Recharge, Abdulganiu A.A. Odunmbaku

Open Access Theses & Dissertations

The extensive use of ground water only began with the advances in pumping technology at the early portion of 20th Century. Groundwater provides the majority of fresh water supply for municipal, agricultural and industrial uses, primarily because of little to no treatment it requires. Estimating the volume of groundwater available in a basin is a daunting task, and no accurate measurements can be made. Usually water budgets and simulation models are primarily used to estimate the volume of water in a basin.

Precipitation, land surface cover and subsurface geology are factors that affect recharge; these factors affect percolation which invariably …

Sedimentology And Stratigraphy Of The Pennsylvanian Saginaw Aquifer, Central Lower Michigan, U.S.A., Niah B. H. Venable

Masters Theses

The Saginaw Aquifer is an important bedrock aquifer serving the needs of over 400,000 people in the Tri-County area of the Central Lower Peninsula of Michigan. The aquifer is comprised of the Pennsylvanian Grand River and Saginaw Formations. This study focuses on expanding existing knowledge of the general sedimentologic and stratigraphic characteristics of these units using conventional geological methods including core analysis, local log to core correlation, local and regional log to log correlation, and biostratigraphy. Analysis of new core from the study area examines facies and depositional environments given cursory coverage in outcrop studies by past researchers.

Incised valley …