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Synthesis, Characterization, Functionalization And Optical Properties Of Silver Nanostructures, Zachary Koontz Aug 2012

Synthesis, Characterization, Functionalization And Optical Properties Of Silver Nanostructures, Zachary Koontz

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The interaction between light and silver nanoparticles via the excitation of plasmon resonances which are the collective oscillation of the free electron density represents the most efficient interaction between light and matter. This alone makes plasmonic silver nanoparticles of great interest for both fundamental studies as well as practical applications. In this thesis, silver nanoparticles of various shapes and sizes and organized clusters were synthesized and investigated for their optical properties.

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A Set Of Tournaments With Many Hamiltonian Cycles, Hayato Ushijima-Mwesigwa Aug 2012

A Set Of Tournaments With Many Hamiltonian Cycles, Hayato Ushijima-Mwesigwa

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For a random tournament on $3^n$ vertices, the expected number of Hamiltonian cycles is known to be $(3^n -1)!/2^{3^n}$. Let $T_1$ denote a tournament of three vertices $ {v_1, v_2, v_3}$. Let the orientation be such that there are directed edges from $v_1 $to $v_2$ , from $v_2$ to $v_3$ and from $v_3$ to $ v_1$. Construct a tournament $T_i$ by making three copies of $T_{i-1}$, $T_{i-1}'$, $T_{i-1}''$ and $T_{i-1}'''$. Let each vertex in $T_{i-1}'$ have directed edges to all vertices in $T_{i-1}''$, similarly place directed edges from each vertex in $T_{i-1}''$ to all vertices in $T_{i-1}'''$ and from $T_{i-1}'''$ …

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Socialq&A: A Novel Approach To Notifiying The Correct Users In Question And Answering Systems, Nikhil Vithlani Aug 2012

Socialq&A: A Novel Approach To Notifiying The Correct Users In Question And Answering Systems, Nikhil Vithlani

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Question and Answering (Q&A) systems are currently in use by a large
number of Internet users. Q&A systems play a vital role in our daily life as
an important platform for information and knowledge sharing. Hence, much
research has been devoted to improving the performance of Q&A systems,
with a focus on improving the quality of answers provided by users, reducing
the wait time for users who ask questions, using a knowledge base to provide
answers via text mining, and directing questions to appropriate users. Due
to the growing popularity of Q&A systems, the number of questions in the
system …

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A Mathematical Framework For Volume Modeling And Simulation, Brandon Pelfrey Aug 2012

A Mathematical Framework For Volume Modeling And Simulation, Brandon Pelfrey

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Rendering, modeling, and simulating processes in spatially-varying media are complex tasks
which typically require tedious mathematical derivations and long development and programming.
In this thesis, a framework is presented which allows for fast and casual exploration of ideas for
volume-based simulation and modeling. Several applications of the framework are shown, including
the simulation of fluid dynamics for computer graphics applications. A procedure for automatically
generating OpenCL code from these is given, along with rudimentary examples.

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Robust Parameter Estimation In The Weibull And The Birnbaum-Saunders Distribution, Jing Zhao Aug 2012

Robust Parameter Estimation In The Weibull And The Birnbaum-Saunders Distribution, Jing Zhao

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This paper concerns robust parameter estimation of the two-parameter Weibull distribution and the two-parameter Birnbaum-Saunders distribution. We use the proposed method to estimate the distribution parameters from (i) complete samples with and without contamination (ii) type-II censoring samples, in both distributions. Also, we consider the maximum likelihood estimation and graphical methods to compare the maximum likelihood estimation and graphical method with the proposed method based on quantile. We find the advantages and disadvantages for those three different methods.

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Novel Data As A Source For Assessing Breeding Phenology Of White-Tailed Deer (Odocoileus Virginianus) In South Carolina, David Stone Aug 2012

Novel Data As A Source For Assessing Breeding Phenology Of White-Tailed Deer (Odocoileus Virginianus) In South Carolina, David Stone

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White-tailed deer (Odocoileus virginianus) breeding phenology varies temporally throughout the species' range and is critical to population management and hunter enjoyment. The South Carolina Department of Natural Resources (SCDNR) demographic and reproductive data, collected primarily from 1970-1992, suggest that 81.86% of conceptions in the Coastal Plain occur between 6 October and 16 November. However, current data regarding conception dates are lacking for a variety of reasons including the current absence of check stations and the use of hunter surveys as the primary means of data collection. To more closely examine recent characteristics of the white-tailed deer breeding season phenology, we …

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Enzyme Actuated Bioresponsive Hydrogels, Andrew Wilson Aug 2012

Enzyme Actuated Bioresponsive Hydrogels, Andrew Wilson

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Bioresponsive hydrogels are emerging with technological significance in targeted drug delivery, biosensors and regenerative medicine. Conferred with the ability to respond to specific biologically derived stimuli, the design challenge is in effectively linking the conferred biospecificity with an engineered response tailored to the needs of a particular application. Moreover, the fundamental phenomena governing the response must support an appropriate dynamic range and limit of detection. The design of these systems is inherently complicated due to the high interdependency of the governing phenomena that guide the sensing, transduction, and the actuation response of hydrogels. To investigate the dynamics of these materials, …

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Development And Characterization Of Shellac-Hydroxypropyl Methyl Cellulose Composite Films With Acid Catalyst, Sana Asrar Aug 2012

Development And Characterization Of Shellac-Hydroxypropyl Methyl Cellulose Composite Films With Acid Catalyst, Sana Asrar

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The objective of this research was to develop a shellac-hydroproyl methyl cellulose (Sh-HPMC) composite film with enhanced water vapor barrier. Citric acid (CA) was used as an acid catalyst, to promote miscibility between HPMC and shellac. In a preliminary test, three different concentrations of CA (1000:1, 200:1, 100:1) were tested to identify the best Sh:CA ratio. Based on the Water vapor permeability properties and mechanical properties, Sh-CA (1000:1 ratio) had the most enhanced water vapor barrier and the lowest reduction in tensile strength compared to the pure HPMC film (control). In the later part of the research, the effect of …

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Lead And Cadmium In Seabirds Of South Africa, Carly Summers Aug 2012

Lead And Cadmium In Seabirds Of South Africa, Carly Summers

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Levels of lead (Pb) and cadmium (Cd) were investigated as potential stressors in adult African penguins (Spheniscus demersus) in the Western Cape Province, South Africa and in nine species of breeding seabirds on Marion Island, South Africa. Seabirds are sentinels of environmental pollution and allow researchers to study contaminant dynamics in marine ecosystems. Many seabirds occupy high trophic positions, which gives them the potential to highlight threats to other apex predators from environmental pollutants. They also accumulate contaminants in higher concentrations because of their greater size and lifespan than may be detectable in lower trophic organisms. Blood samples were collected …

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Biogeochemical Processes In Hydrosoil Of A Pilot-Scale Constructed Wetland Treatment System Designed For Treatment Of Metals, Kristen Jurinko Aug 2012

Biogeochemical Processes In Hydrosoil Of A Pilot-Scale Constructed Wetland Treatment System Designed For Treatment Of Metals, Kristen Jurinko

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Environmental conditions, metal (Cd, Cu, Ni, and Zn) distribution, and metal fractionation in hydrosoil (sediment and overlying organic detritus) of a free water surface pilot-scale constructed wetland treatment system (CWTS) were investigated to determine treatment processes. Chemical and mineralogical analyses were performed on organic detritus samples and sediment cores collected from two cells planted with Schoenoplectus californicus and two cells planted with Typha angustifolia. T-tests indicate that cells planted with S. californicus and those planted with T. angustifolia were equally effective in promoting conditions in the detritus favorable for sorption of metals and complexation with acid-volatile sulfide (AVS). For the …

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Load Carrying Capacity Assessment Of A Masonry Dome, Tun Li Aug 2012

Load Carrying Capacity Assessment Of A Masonry Dome, Tun Li

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This thesis first establishes a semi-empirical relationship to estimate the reduction in load carrying capacity of a masonry dome due to damage by exploiting deviations in the fundamental natural frequency. A macro finite element model of the dome is developed and calibrated using both non-destructive vibration measurements and destructive load-displacement measurements up to failure. The macro-model is then executed to simulate incremental development of cracks. The first natural frequency and remaining load carrying capacity of the dome are monitored to define a semi-empirical relationship, which is ultimately generalized for spherical domes with varying span-to-height ratios.
Subsequently, in order to numerically …

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The Role Of Early Head Start In School Readiness, Meron Habtu Aug 2012

The Role Of Early Head Start In School Readiness, Meron Habtu

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This thesis considers the relationship between participation in Early Head Start programs and school readiness for children from low-income families. The work uses longitudinal data from the Early Childhood Research and Evaluation (EHSRE) project that followed 3001 families in 17 Early Head Start Centers from 1996-2010. In the project, data was collected about children's school readiness in three phases: 0-3 years, Pre-K and fifth grade.
In the sample data set, families were randomly assigned to either a treatment group of Early Head Start participants or a control group. Empirical analysis was conducted that compares the test scores of the treatment …

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Fault Analysis Of An Unbalanced Distribution System With Distributed Generation, Parimal Saraf Aug 2012

Fault Analysis Of An Unbalanced Distribution System With Distributed Generation, Parimal Saraf

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In recent years there has been a lot of emphasis on renewable power integration due to environmental issues and to lower the dependence on fossil fuels. The presence of renewable sources in the distribution systems adds complexity to the calculation of the power flows and hence has a direct impact on the short circuit calculations, protection and control. The presence of unbalance in distribution systems worsens the situation since the three phase voltages and currents are no longer equal in magnitude and 120 degrees phase shifted.
This thesis involves a fault study in a 14-bus distribution system with integrated wind …

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Evaluation Of Use Of Em38-Mk2 As A Tool To Understand Field Scale Changes In Soil Properties, Sudershan Gangrade Aug 2012

Evaluation Of Use Of Em38-Mk2 As A Tool To Understand Field Scale Changes In Soil Properties, Sudershan Gangrade

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Sustainable water resources management requires tools to help farmers identify variations in soil hydraulic characteristics so that precision irrigation schemes can be developed to optimize water use. In this study we use electromagnetic induction (EMI) to evaluate whether changes in the apparent electrical conductivity (σ_a) of agricultural fields can be related to hydrologic processes. Field work for this study was completed at three different sites - 1) in different agricultural fields located in a watershed near Salri, Madhya Pradesh, India, 2) over an agricultural field located near Clemson University, SC, and 3) at a flood plain wetland restoration site near …

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Selenium Removal In Nutrient-Amended Pilot-Scale Constructed Wetland Treatment Systems, Peter Van Heest Aug 2012

Selenium Removal In Nutrient-Amended Pilot-Scale Constructed Wetland Treatment Systems, Peter Van Heest

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ABSTRACT
In a year-long study, pilot-scale constructed wetland treatment systems (CWTSs) targeted removal of selenium (Se) from a simulated impaired water through dissimilatory Se reduction. Effects of temperature and precipitation on the treatment of Se in the CWTSs were investigated. The experimental design consisted of CWTSs amended with a fermented yeast product (AquaSmartTM, Diamond V¨, Cedar Rapids, IA), which served as a nutrient source for Se-reducing bacteria, at mass loadings of 1.75, 3.5, 5.25, 7, and 8.75 mg/min. The 5 µg/L treatment goal for CWTS outflow concentration was measured in 69 of 378 samples taken from all CWTSs. Of the …

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Biomarker Effects In Sunfish And Bass From The Saluda River, Sc, Jessica Mierzejewski Aug 2012

Biomarker Effects In Sunfish And Bass From The Saluda River, Sc, Jessica Mierzejewski

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The upstate and Piedmont region of South Carolina is a rapidly urbanizing area with a fast growing population. This increase in population and development has the potential to negatively impact the aquatic system due to increased pollution from runoff and effluents from industrial, manufacturing and wastewater treatment facilities. In 2009 the Saluda River, a major river in this area of the state, was ranked 6th of America's most endangered rivers by American Rivers. This ranking was largely due to high phosphorus levels in the river, though there are many sources of pollution that may be affecting the river ecosystem. The …

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Local Polynomial Regression With Application To Sea Surface Temperatures, Michael Finney Aug 2012

Local Polynomial Regression With Application To Sea Surface Temperatures, Michael Finney

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Our problem involves methods for determining the times of a maximum or minimum for a general mean function in time series data. The methods explored here involve polynomial smoothing. In theory, the methods calculate a general number of derivatives of the estimated polynomial. Using these techniques, we wish to find a balance between error, variance, and complexity and apply it to a time series of sea surface temperatures. We will first explore the theory behind the method and then find a way to optimally apply it to our data.

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Star-Disk Interaction In Herbig Ae/Be Stars, Christa Speights Aug 2012

Star-Disk Interaction In Herbig Ae/Be Stars, Christa Speights

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The question of the mechanism of certain types of stars is important. Classical T Tauri (CTTS) stars accrete magnetospherically, and Herbig Ae/Be stars (higher-mass analogs to CTTS) are thought to also accrete magnetospherically, but the source of a kG magnetic field is unknown, since these stars have radiative interiors. For magnetospheric accretion, an equation has been derived (Hartmann, 2001) which relates the truncation radius, stellar radius, stellar mass, mass accretion rate and magnetic field strength.
Currently the magnetic field of Herbig stars is known to be somewhere between 0.1 kG and 10 kG. One goal of this research is to …

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Intense And Highly Energetic Atmospheric Pressure Plasma Jet Arrays, John Furmanski Aug 2012

Intense And Highly Energetic Atmospheric Pressure Plasma Jet Arrays, John Furmanski

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This thesis documents the efforts taken to produce highly ionized and concentrated atmospheric pressure plasma using an arrayed atmospheric pressure plasma jet (APPJ) system. The honeycomb-shaped array features seven plasma jets operating in close enough proximity to one another to exhibit jet-to-jet coupling behavior. Optimal gas flow rates for the system were determined and intense plasma plumes composed of argon and/or helium are generated. Optical emission spectroscopy was employed to observe the charged particles responsible for the emissions of each gas discharge and APPJ operation mode. Plasma etching of indium tin oxide glass was conducted to verify the highly energetic …

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Branching Rules For Minimum Congestion Multi-Commodity Flow Problems, Cameron Megaw Aug 2012

Branching Rules For Minimum Congestion Multi-Commodity Flow Problems, Cameron Megaw

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In this paper, we examine various branch and bound algorithms for a minimum congestion origin-destination integer multi-commodity flow problem.
The problem consists of finding a routing such that the congestion of the most congested arc is minimum. For our implementation, we assume that all demands are known a priori.
We provide a mixed integer linear programming formulation of our problem and propose various new branching rules to solve the model. For each rule, we provide theoretical and experimental proof of their effectiveness.
In order to solve large instances, that more accurately portray real-world applications, we outline a path formulation model …

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Software Testability Measure For Sae Architecture Analysis And Design Language (Aadl)Software Testability Measure For Sae Architecture Analysis And Design Language (Aadl), Hung Vo Aug 2012

Software Testability Measure For Sae Architecture Analysis And Design Language (Aadl)Software Testability Measure For Sae Architecture Analysis And Design Language (Aadl), Hung Vo

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Testability is an important quality attribute of software, especially for critical systems such as avionics, medical, and automotive. Improvement in the early testability of software architecture, the first artifact of the software system, will help reduce issues and costs later in the development process.
AADL, an architecture analysis description language suitable for critical embedded, real-time systems, can be used for design documentation, analysis and code generation. Because the capability of AADL can be extended, it is possible to add new analyses to its core language. Tools such as the Open Source AADL Tool Environment (OSATE) provide plugins for processing AADL …

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Synthesis And Applications Of Novel Silver Nanoparticle Structures, Kyle Dukes Aug 2012

Synthesis And Applications Of Novel Silver Nanoparticle Structures, Kyle Dukes

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ABSTRACT
The field of nanotechnology is rapidly expanding across disciplines as each new development is realized. New exciting technologies are being driven by advances in the application of nanotechnology; including biochemical, optical, and semiconductors research. This thesis will focus on the use of silver nanoparticles as optical labels on cells, methods of forming different small structures of silver nanoparticles, as well as the use of silver nanoparticles in the development of a photovoltaic cell.
Silver nanoparticles have been modified with self-assembled monolayers of hydroxyl-terminated long chain thiols and encapsulated with a silica shell. The resulting core-shell nanoparticles were used as …

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Development Of Enrichment Cultures For Anaerobic Reductive Dechlorination Of Tetrachloroethene Under Low Ph Conditions, Chen Jiang Aug 2012

Development Of Enrichment Cultures For Anaerobic Reductive Dechlorination Of Tetrachloroethene Under Low Ph Conditions, Chen Jiang

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Bioremediation is an attractive remediation strategy for groundwater contaminated with tetrachloroethene (PCE) since it can result in complete reductive dechlorination to non-hazardous ethene, often at a lower cost than other treatment methods. The optimum pH for microbes that chlororespire chlorinated ethenes is in the range of 6.5-7.5. However, the groundwater at many locations is outside this range, and typically on the low side. Addition of a base to increase the pH is problematic due to the difficulty of achieving homogenous distribution and the potential for clogging caused by precipitation. The objectives of this thesis were 1) to develop anaerobic enrichment …

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Reproductive Ecology Of American Oystercatchers In The Cape Romain Region Of South Carolina: Implications For Conservation, Samantha Collins Aug 2012

Reproductive Ecology Of American Oystercatchers In The Cape Romain Region Of South Carolina: Implications For Conservation, Samantha Collins

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The Cape Romain Region (CRR) is located along the coast of South Carolina and supports over half of the breeding pairs (approximately 200 pairs) of American Oystercatchers (Haematopus palliatus) in the state. Research has shown that oystercatcher productivity in this area is low due to predation and over-wash from high tides and boat wakes. I assessed the feasibility of using headstarting as a means of reducing nest loss in an attempt to enhance reproductive success during the 2010 and 2011 breeding seasons. Apparent nest success of headstarted nests (52%) was higher than control nests (11%) along two study areas within …

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Fast And Efficient Classification, Tracking, And Simulation In Wireless Sensor Networks, Hao Jiang Aug 2012

Fast And Efficient Classification, Tracking, And Simulation In Wireless Sensor Networks, Hao Jiang

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Wireless sensor networks are composed of large numbers of resource-lean sensors that collect low-level inputs from the physical world. The applications present challenges for programmers. On the one hand, lightweight algorithms are required given the limited capacity of the constituent devices. On the other, the algorithms must be scalable to accommodate large networks. In this thesis, we focus on the design and implementation of fast and lean (yet scalable) algorithms for classification, simulation, and target tracking in the context of wireless sensor networks. We briefly consider each of these challenges in turn.
The first challenge is to achieve high precision …

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Probing And Controlling Fluid Rheology At Microscale With Magnetic Nanorods, Alexander Tokarev Aug 2012

Probing And Controlling Fluid Rheology At Microscale With Magnetic Nanorods, Alexander Tokarev

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This Dissertation is focused on the development of new methods for characterization and control of fluid rheology using magnetic nanorods. This Dissertation consists of five chapters. In the first chapter, we review current microrheologial methods and develop a Magnetic Rotational Spectroscopy (MRS) model describing nanorod response to a rotating magnetic field. Using numerical modeling, we analyze the effects of materials parameters of nanorods and fluids on the MRS characteristic features. The model is designed for a specific experimental protocol. We introduce and examine physical parameters which can be measured experimentally. The model allows identification of MRS features enabling the calculation …

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A Formative Experiment To Promote Disciplinary Literacy In Middle-School And Pre-Service Teacher Education Through Blogging, Jamie Colwell Aug 2012

A Formative Experiment To Promote Disciplinary Literacy In Middle-School And Pre-Service Teacher Education Through Blogging, Jamie Colwell

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This dissertation describes a formative experiment that investigated how strategy instruction paired with collaborative blogging could promote disciplinary literacy among eighth-grade students in a social studies classroom and among pre-service teachers in a social studies methods course. Qualitative methods were utilized to collect and analyze data in this study. To determine modifications to the intervention, an embedded, single-case study was designed to analyze data iteratively using constant comparative methods. Post-study, qualitative methods were also used to conduct retrospective analysis to connect overall findings to theory. Three modifications were made, in the middle-school setting, to the intervention, which enhanced participants' progress …

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Elasto-Capillarity In Fibrous Materials, Daria Monaenkova Aug 2012

Elasto-Capillarity In Fibrous Materials, Daria Monaenkova

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Current advances in the manufacture of nanoporous and nanofibrous materials with high absorption capacity open up new opportunities for the development of fiber-based probes and sensors. Pore structures of these materials can be designed to provide high suction pressure and fast wicking. During wicking, due to the strong capillary action, the liquids exert stresses on the fiber network, thus the stressed state of dry and wet parts of the material differs. In this work the effect of stress reduction in fibrous materials due to the presence of wetting liquid in the pore structure is studied in details for both static …

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The Influence Of Land Use On Fish Health And Fish Communities In Wadeable Steams In South Carolina, Andrew Sayer Aug 2012

The Influence Of Land Use On Fish Health And Fish Communities In Wadeable Steams In South Carolina, Andrew Sayer

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In 2011 the State of South Carolina population was over 4.6 million people and has increased at a rate of around 15% (1.5% per year) throughout the last decade. While the population density per square mile is relatively low compared to other US states, it seems certain the population will further increase in years to come. Increasing population density leads to urbanization resulting in an increase in impervious surfaces such as roadways, parking lots, and building roofs. This changing land use can have dramatic effects on smaller streams and creeks which form the upper reaches of watersheds. Although water systems …

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Environmental Implications And Applications Of Nanomaterials, Priyanka Bhattacharya Aug 2012

Environmental Implications And Applications Of Nanomaterials, Priyanka Bhattacharya

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Recent advances in material science and nanotechnology have given rise to a myriad of developments, while in the meantime call for research into the impacts of nanomaterials on the environment and human health. Although considerable progress has been made in the past decade concerning the behavior of nanomaterials in biological systems, such understanding is critically lacking with respect to the fate of nanomaterials in ecosystems.
Accordingly, this dissertation addresses the interactions between nanomaterials and algae--the major constituent of the aquatic food chain (Part I, Chapter two), and exploits the physicochemistry of nanoscaled synthetic dendritic polymers for environmental applications, especially for …

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