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Quartz Grain Microtextures And Sediment Provenance: Using Scanning Electron Microscopy To Characterize Tropical Highland Sediments From Costa Rica And The Dominican Republic, Sarah Marie Deane 2010 University of Tennessee - Knoxville

Quartz Grain Microtextures And Sediment Provenance: Using Scanning Electron Microscopy To Characterize Tropical Highland Sediments From Costa Rica And The Dominican Republic, Sarah Marie Deane

Masters Theses

Microtextures recorded on quartz sand grain surfaces provide evidence of past environment. Environmental processes, such as transport by glacial ice, create unique microtextures on sand grain surfaces that can be observed under high magnification with a scanning electron microscope. These microtextures and their proportions tend to be unique to environment type, allowing investigators to infer the environmental conditions to which sediments have been exposed, for example to distinguish sediments from fluvial versus mass-wasted environments. Microtextural evidence also allows inferences about the history of sediments of unknown origin.

This thesis determines the qualitative and quantitative microtextural fingerprint of glacigenic quartz sand ...


Aquatic Habitat Mapping Within The Obed Wild And Scenic River For Threatened And Endangered Species Habitat Delineation, Joseph Ross Candlish 2010 University of Tennessee, Knoxville

Aquatic Habitat Mapping Within The Obed Wild And Scenic River For Threatened And Endangered Species Habitat Delineation, Joseph Ross Candlish

Masters Theses

There is a need to define a more efficient and accurate approach to aquatic habitat mapping. Traditional approaches have focused on intense biological/non-biological sampling and observation analysis within specific and restrained scales. Therefore, an underwater video mapping system (UVMS) has been developed in efforts to identify federally protected aquatic species’ habitats within the Obed Wild and Scenic River (OBRI). The UVMS kayak apparatus provides georeferenced video footage correlated with GPS (global positioning systems) for GIS (geographic information systems) mapping applications. Based on its fluvial and geomorphological trends, OBRI was dissected quantitatively and integrated into databases for species-specific GIS habitat ...


Rapid Cooling Of The Neutron Star In The Quiescent Super-Eddington Transient Xte J1701-462, Joel K. Fridriksson, Jeroen Homan, Rudy Wijnands, Mariano Méndez, Diego Altamirano, Edward M. Cackett, Edward F. Brown, Tomaso M. Belloni, Nathalie Degenaar, Walter H. G. Lewin 2010 Massachusetts Institute of Technology

Rapid Cooling Of The Neutron Star In The Quiescent Super-Eddington Transient Xte J1701-462, Joel K. Fridriksson, Jeroen Homan, Rudy Wijnands, Mariano Méndez, Diego Altamirano, Edward M. Cackett, Edward F. Brown, Tomaso M. Belloni, Nathalie Degenaar, Walter H. G. Lewin

Physics and Astronomy Faculty Research Publications

We present Rossi X-Ray Timing Explorer and Swift observations made during the final three weeks of the 2006-2007 outburst of the super-Eddington neutron star (NS) transient XTE J1701-462, as well as Chandra and XMM-Newton observations covering the first sime800 days of the subsequent quiescent phase. The source transitioned quickly from active accretion to quiescence, with the luminosity dropping by over 3 orders of magnitude in sime13 days. The spectra obtained during quiescence exhibit both a thermal component, presumed to originate in emission from the NS surface, and a non-thermal component of uncertain origin, which has shown large and irregular variability ...


Radial Heterogeneity And Surface Properties Of Columns Used In High Performance Liquid Chromatography, Jude A. Abia 2010 University of Tennessee - Knoxville

Radial Heterogeneity And Surface Properties Of Columns Used In High Performance Liquid Chromatography, Jude A. Abia

Doctoral Dissertations

The radial heterogeneity of some columns used in high performance liquid chromatography (HPLC) was investigated using an on-column microelectrochemical amperometric detector. Such a detector allowed the recording of the elution profiles at different spatial positions throughout the column exit cross-section. From this, we obtain information about the radial distribution of the mobile phase velocity, column efficiency, and analyte concentration. In all cases, the results obtained show that the spatial distribution of the mobile phase velocity does not follow a piston-flow behavior but exhibits radial heterogeneity with differences not exceeding 5% between the center and wall regions of any column. The ...


Using Ant Colonization Optimization To Control Difficulty In Video Game Ai., Joshua Courtney 2010 East Tennessee State University

Using Ant Colonization Optimization To Control Difficulty In Video Game Ai., Joshua Courtney

Undergraduate Honors Theses

Ant colony optimization (ACO) is an algorithm which simulates ant foraging behavior. When ants search for food they leave pheromone trails to tell other ants which paths to take to find food. ACO has been adapted to many different problems in computer science: mainly variations on shortest path algorithms for graphs and networks.

ACO can be adapted to work as a form of communication between separate agents in a video game AI. By controlling the effectiveness of this communication, the difficulty of the game should be able to be controlled. Experimentation has shown that ACO works effectively as a form ...


Gene Expression In Hypothalamus, Liver, And Adipose Tissues And Food Intake Response To Melanocortin-4 Receptor Agonist In Pigs Expressing Melanocortin-4 Receptor Mutations, C. Richard Barb, Gary J. Hausman, Romdhane Rekaya, Clay A. Lents, Sender Lkhagvadorj, Long Qu, Weiguo Cai, Oliver P. Couture, Lloyd L. Anderson, Jack C. M. Dekkers, Christopher K. Tuggle 2010 United States Department of Agriculture

Gene Expression In Hypothalamus, Liver, And Adipose Tissues And Food Intake Response To Melanocortin-4 Receptor Agonist In Pigs Expressing Melanocortin-4 Receptor Mutations, C. Richard Barb, Gary J. Hausman, Romdhane Rekaya, Clay A. Lents, Sender Lkhagvadorj, Long Qu, Weiguo Cai, Oliver P. Couture, Lloyd L. Anderson, Jack C. M. Dekkers, Christopher K. Tuggle

Animal Science Publications

Transcriptional profiling was used to identify genes and pathways that responded to intracerebroventricular injection of melanocortin-4 receptor (MC4R) agonist [Nle4, D-Phe7]-α-melanocyte stimulating hormone (NDP-MSH) in pigs homozygous for the missense mutation in the MC4R, D298 allele (n = 12), N298 allele (n = 12), or heterozygous (n = 12). Food intake (FI) was measured at 12 and 24 h after treatment. All pigs were killed at 24 h after treatment, and hypothalamus, liver, and back-fat tissue was collected. NDP-MSH suppressed (P < 0.004) FI at 12 and 24 h in all animals after treatment. In response to NDP-MSH, 278 genes in hypothalamus (q ≤ 0.07, P ≤ 0.001), 249 genes in liver (q ≤ 0.07, P ≤ 0.001), and 5,066 genes in ...


Biology And Ecology Of Lake Sturgeon Acipenser Fulvescens In The Grasse River, New York, Drew Trested 2010 Clemson University

Biology And Ecology Of Lake Sturgeon Acipenser Fulvescens In The Grasse River, New York, Drew Trested

All Dissertations

The objectives of this dissertation were to (1) evaluate the age, growth, mortality, and abundance of lake sturgeon Acipenser fulvescens in the Grasse River, New York; (2) characterize seasonal movement patterns and mesohabitat use for adult and juvenile lake sturgeon in the Grasse River, New York; and (3) quantify the immediate and delayed post-procedure mortality for shovelnose sturgeon after insertion of an endoscope through an incision. I determined age for 196 of 211 lake sturgeon by examination of sectioned pectoral fin rays. Ages ranged from 0 -32 years and the annual mortality rate for fish between ages 7 and 14 ...


Mobility Of Plutonium In Zea Mays (Corn): Determination Of Transport Velocities, Spatial Distribution And Correlations With Iron., Shannon Thompson 2010 Clemson University

Mobility Of Plutonium In Zea Mays (Corn): Determination Of Transport Velocities, Spatial Distribution And Correlations With Iron., Shannon Thompson

All Dissertations

Understanding the environmental behavior of plutonium (Pu) is essential for proper radioactive waste disposal or for remedial activities following an accidental release of Pu. The environmental behavior of Pu is influenced by physical, chemical, and biotic factors, such as the simultaneous existence of multiple Pu species, redox transformations at mineral surfaces, colloid formation, and the potential of microbes and plants to affect its sorption to soil. Plant Pu studies have been conducted for quantifying bioaccumulation or phytoremediation. Until now, experimental studies have not focused on the capacity of plants to affect the transport behavior and distribution of Pu in the ...


Development Of A Spatialy Explicit Habitat Patch Model (C-Pan) And Comparative Analysis Of Patch Modeling Techniques: The Crafting Of A New Tool For Conservation Planners, Ryan Perkl 2010 Clemson University

Development Of A Spatialy Explicit Habitat Patch Model (C-Pan) And Comparative Analysis Of Patch Modeling Techniques: The Crafting Of A New Tool For Conservation Planners, Ryan Perkl

All Dissertations

ABSTRACT
Ecological theories including island biogeography, intermediate disturbance, metapopulation and metacommunity all suggest that habitat patches of larger size and those comprised of substantial configurations of interior or core habitat possess the greatest potential for long-term species viability. As a direct means of mitigating edge encroachment and fragmentation's other adverse effects, there is a growing consensus among conservation planners that assembling larger, more cohesive tracts with substantial core area is of ecological value in conservation planning. Larger and more cohesive patches are believed to sustain larger and more viable local populations, enhance overall biodiversity, incorporate a wider array of ...


Synthesis Of Meta-Terphenyl Scaffolded Molecules For Catalysis And Sensor Applications, Brad Morgan 2010 Clemson University

Synthesis Of Meta-Terphenyl Scaffolded Molecules For Catalysis And Sensor Applications, Brad Morgan

All Dissertations

The utility of the m-terphenyl has been observed in a wide variety of applications since its first discovery. The tunable conformational flexibility contributes to the unique properties and resulting applications thereof. Chapter 1 goes into detail about the concepts used throughout and defines the tools needed to understand the chemistry in the
resulting chapters.
The primary use of the m-terphenyl herein is as a canopy that shields a pocket created underneath the central ring. Functionalization within this pocket allows metal binding in defined coordination environments. with the use of donor ligands attached to the flanking rings. The applications of these ...


Analysis Of Fresh Water Resources At The Line Hole Well Field, San Salvador Island, The Bahamas, Scot Allan Russell Jr. 2010 Western Kentucky University

Analysis Of Fresh Water Resources At The Line Hole Well Field, San Salvador Island, The Bahamas, Scot Allan Russell Jr.

Masters Theses & Specialist Projects

A major economic constraint in the Bahamas, and other small carbonates islands world-wide, is the lack of fresh water resources. To combat these socio-economic problems on San Salvador Island I sought to gain a more detailed understanding of the extent, behavior, and controls on the island’s fresh-water lens. DC electrical resistivity tomography and time-series geochemical data are used to study the fresh water lens at the Line Hole well field. Electrical Resistivity profiles are used to image the extent of fresh water resources. Time-series geochemical data provide information on the behavior of the fresh water resources as a function ...


A Novel Pervious Cement Reaction Barrier (Pcrb) In Situ Arsenic Remediation System, Morgan Liane Jones 2010 Western Kentucky University

A Novel Pervious Cement Reaction Barrier (Pcrb) In Situ Arsenic Remediation System, Morgan Liane Jones

Masters Theses & Specialist Projects

No abstract provided.


Hidra: Hierarchical Inter-Domain Routing Architecture, Bryan Clevenger 2010 California Polytechnic State University - San Luis Obispo

Hidra: Hierarchical Inter-Domain Routing Architecture, Bryan Clevenger

Master's Theses and Project Reports

As the Internet continues to expand, the global default-free zone (DFZ) forwarding table has begun to grow faster than hardware can economically keep pace with. Various policies are in place to mitigate this growth rate, but current projections indicate policy alone is inadequate. As such, a number of technical solutions have been proposed. This work builds on many of these proposed solutions, and furthers the debate surrounding the resolution to this problem. It discusses several design decisions necessary to any proposed solution, and based on these tradeoffs it proposes a Hierarchical Inter-Domain Routing Architecture - HIDRA, a comprehensive architecture with a ...


Hopping Conductivity And Charge Transport In Low Density Polyethylene, Jerilyn Brunson 2010 Utah State University

Hopping Conductivity And Charge Transport In Low Density Polyethylene, Jerilyn Brunson

All Graduate Theses and Dissertations

The properties and behaviors of charge transport mechanisms in highly insulating polymers are investigated by measuring conduction currents through thin film samples of low density polyethylene (LDPE). Measurements were obtained using a constant voltage method with copper electrodes inside a chamber adapted for measurements under vacuum and over a wide range of temperatures and applied fields. Field-dependent behaviors, including Poole-Frenkel conduction, space charge limited current (SCLC), and Schottky charge injection, were investigated at constant temperature. These field-dependent mechanisms were found to predict incorrect values of the dielectric constant and the field dependence of conductivity in LDPE was not found to ...


Classification And Fertility Of Soils In The Big South Fork National River And Recreation Area Based On Landscape Position And Geology, Ryan H. Blair 2010 The University of Tennessee, Biosystems Engineering and Soil Science

Classification And Fertility Of Soils In The Big South Fork National River And Recreation Area Based On Landscape Position And Geology, Ryan H. Blair

Masters Theses

The Big South Fork National River and Recreation Area encompasses more than 50,585 hectares (125,000 acres) of the Cumberland Plateau along the border of Tennessee and Kentucky. Highly dissected and steep terrain have made accessibility to much of the park limited, thus little work has been done to investigate the formation of these soils. Seven native soil profiles were selected for chemical and physical analysis representing Pennsylvanian-aged acidic sandstone and shale geology and landforms. The objectives of this study included the characterization of selected native profiles by physical and chemical analysis, as well as classification using US Soil ...


Facilitating Behavior Change Of Coastal Communities In Regards To Climatic Hazards, Marisa Nixon 2010 University of Rhode Island

Facilitating Behavior Change Of Coastal Communities In Regards To Climatic Hazards, Marisa Nixon

Senior Honors Projects

For my Senior Honors Project I participated in the Climate Change Collaborative, which is a new interdisciplinary research project studying the ways in which coastal communities in Rhode Island can better adapt to the environmental, cultural and economic consequences of climate change. As a member of this collaborative, I worked in a vertically integrated team of faculty (psychology researchers, climate scientists and communications science practitioners and researchers) as well as undergraduate and graduate students, to begin an endeavor through which behavior change will be assessed in regards to climate change. For the purposes of this study, we specifically focus on ...


Three Essays On Environmental- And Spatial-Based Valuation Of Urban Land And Housing, Lu Liu 2010 Utah State University

Three Essays On Environmental- And Spatial-Based Valuation Of Urban Land And Housing, Lu Liu

All Graduate Theses and Dissertations

This dissertation attempts to provide a comprehensive examination on the non-market valuation of the effect of open space amenities and local public infrastructure on the value of urban land and housing with both spatial heterogeneity and project heterogeneity. The demand for raw land is a derived demand for housing built on it. Therefore, we need to examine the land market and the housing market together. On the one hand, we estimate the value of urban land in a market that does not satisfy the usual assumptions of a competitive market structure as well as incentive incompatibility issues for transaction participants ...


Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards 2010 Utah State University

Dancing With Heretics: Essays On Orthodoxy, Questioning And Faith, Darren M. Edwards

All Graduate Theses and Dissertations

While much has been written about the conflicts, supposed or actual, between logic and faith, science and religion, few accounts of the personal turmoil these conflicts can cause exist. Likewise, many of these nonfiction accounts are written from a distinctly polarized place leaning either to science or faith.

In this thesis, I mix research and history with memoir and a sense of poetry to explore my personal experience with this conflict. At its outset, I hoped for this project to capture my struggle as an orthodox member of The Church of Jesus Christ of Latter-day Saints (LDS) in dealing with ...


Random Forests Applied As A Soil Spatial Predictive Model In Arid Utah, Alexander Knell Stum 2010 Utah State University

Random Forests Applied As A Soil Spatial Predictive Model In Arid Utah, Alexander Knell Stum

All Graduate Theses and Dissertations

Initial soil surveys are incomplete for large tracts of public land in the western USA. Digital soil mapping offers a quantitative approach as an alternative to traditional soil mapping. I sought to predict soil classes across an arid to semiarid watershed of western Utah by applying random forests (RF) and using environmental covariates derived from Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and digital elevation models (DEM). Random forests are similar to classification and regression trees (CART). However, RF is doubly random. Many (e.g., 500) weak trees are grown (trained) independently because each tree is trained with a new ...


Nutrient Utilization From Anaerobic Digester Effluent Through Algae Cultivation, Shantanu Wahal 2010 Utah State University

Nutrient Utilization From Anaerobic Digester Effluent Through Algae Cultivation, Shantanu Wahal

All Graduate Theses and Dissertations

Nutrients present in digested animal waste can be utilized for algae cultivation under suitable conditions. Algal growth, however, depends on the chemical forms and speciation of these nutrients. In this study a chemical equilibrium model was first used to describe nutrient speciation and predict conditions that enhance the solubility of nutrients in anaerobic digester effluent. Dilution with water and separation of large particulates greatly improved nutrient availability and light penetration - conditions favorable for algal cultivation. Algae growth was tested using three strains - Scenedesmus dimorphous (UTEX # 417), Chlorella vulgaris (UTEX# 265), and an algal isolate (designated as LLAI and later identified ...


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