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2013

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Articles 8401 - 8430 of 11462

Full-Text Articles in Physical Sciences and Mathematics

An Evaluation Of Spatial Variability Of Water Stress Index Across The United States: Implications Of Supply And Demand In The East Vs The West, Jennifer Ann Roath Jan 2013

An Evaluation Of Spatial Variability Of Water Stress Index Across The United States: Implications Of Supply And Demand In The East Vs The West, Jennifer Ann Roath

Open Access Theses

In order to support both human and environmental needs, high quality fresh water must be available when and where it is required. As a metric for indicating unsustainable water usage, WSI is only useful when the values reflect accurate interactions between supply and demand; however, the complexity of temporal and spatial variability of available fresh water complicates the analysis of water stress.

The overall goal of this project was to investigate the spatial variability of water stress across the United States and the appropriate spatial scale for management decisions. To accomplish this, a national dataset describing spatial distribution and breakdown …


Sanitation Infrastructure, Medicinal Plant Use And Diarrhea In Rural Costa Rican Communities, Travis Clifford Sondgerath Jan 2013

Sanitation Infrastructure, Medicinal Plant Use And Diarrhea In Rural Costa Rican Communities, Travis Clifford Sondgerath

Open Access Theses

Diarrhea is estimated to be responsible for 3.3 million deaths a year and is particularly problematic in the developing world among children. The Millennium Development Goals established by the United Nations has set a goal of reducing mortality among children by two thirds during the new millennium. However due to the nature of diarrhea it is often difficult to study its patterns, distribution, and determinants.

This study presents an analysis of the relationship between diarrhea and sanitation infrastructure and medicinal plant use in 4 rural Costa Rican communities. Over the past few decades' access to clean drinking water and municipal …


The Influence Of The Tibetan Plateau Elevation On The Global And Asian Monsoons, Rene Paul Acosta Jan 2013

The Influence Of The Tibetan Plateau Elevation On The Global And Asian Monsoons, Rene Paul Acosta

Open Access Theses

It has been long hypothesized that large-scale topographic changes, such as the surface uplift of the Tibetan Plateau, impacts the development of the South Asian and East Asian monsoons and influences other monsoon regions. However, recent modeling has shown that spatial distribution of the global monsoon, which includes the South Asian and East Asian monsoons is largely unaffected by the elevation of the plateau. In this study, we present results from a series of modern day simulations using CESM1.0 in a mixed-layer (slab ocean) configuration. The Tibetan Plateau height is varied from double that of the modern maximum plateau elevation …


Integrating The Sap Software Into The Manufacturing Engineering Curriculum, Lin Qian Jan 2013

Integrating The Sap Software Into The Manufacturing Engineering Curriculum, Lin Qian

Open Access Theses

The concept of Enterprise Resource Planning (ERP) was developed to integrate data efficiently and eliminate redundancy within organizations. Worldwide industries rely on ERP systems to keep a competitive advantage in world market place. Besides, cross-functional knowledge is required in industry. It is critical that schools integrate ERP concepts and methods in to academic curricula for Technology and Engineering School.

This thesis examined the effectiveness of a simulation game as a method for teaching for ERP systems in Technology and Engineering. The quasi-experimental design was used in this study to determine if the SAP simulation game had an impact on students' …


A Qualitative Perspective Of Sustainability Across A Supply Chain, Colton Michael Schliep Jan 2013

A Qualitative Perspective Of Sustainability Across A Supply Chain, Colton Michael Schliep

Open Access Theses

Schliep, Colton M. M.S., Purdue University, May 2013. A Qualitative Perspective of Sustainability Across a Supply Chain. Major Professors: Dr. Edie K. Schmidt and Dr. Edward Sweeney.

Using a qualitative approach, this investigation examines perspectives of sustainability concepts and industry experiences from people in various supply chain roles, attempting to answer the question, "How does sustainability, as a practice and definition, differ across a supply chain; and what are its benchmarks?" Participants in the study included 5 working professionals across different industries. Using systems analysis, in depth interviews elicited 12 common themes of the research. Outcomes of the research discuss …


Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt Jan 2013

Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt

Open Access Theses

Factors of ion specificity and ionic strength (I~0-100) were studied in the electrostatic complex formation and protein particle formation by thermal treatment for a β-lactoglobulin and pectin system. ζ-potential showed β-lactoglobulin and pectin began to interact near pH 5.50 and interactions were strengthened with decrease in pH. Visible light turbidimetry and light scattering at 90° revealed a trend in critical pH transitions for electrostatic complex formation based on both the ionic strength and the anion of the salt species, while effects of the monovalent cation was insignificant. Critical pH values for complex formation and separation (pHc and pHΦ) decreased with …


Analysis Of Android Update Packages As A Method To Load Forensic Utilities And Malicious Applications To An Android Device, Mark Lohrum Jan 2013

Analysis Of Android Update Packages As A Method To Load Forensic Utilities And Malicious Applications To An Android Device, Mark Lohrum

Open Access Theses

Android devices are extremely popular and are projected to stay popular. Both forensic tools and malware exist designed specifically for Android devices. The purpose of this study is to explore a new method of loading forensic tools and malware to Android devices. This new method is the update module, which is used to install updates to the operating system. This thesis proposed and completed research to test four different custom update packages on three different Android devices. Two of the update packages contain forensic utilities and the other two contain malicious tools. An update package collecting web history using the …


The Role Of Test Administrator And Error, Michael Edward Brockly Jan 2013

The Role Of Test Administrator And Error, Michael Edward Brockly

Open Access Theses

This study created a framework to quantify and mitigate the amount of error that test administrators introduced to a biometric system during data collection. Prior research has focused only on the subject and the errors they make when interacting with biometric systems, while ignoring the test administrator. This study used a longitudinal data collection, focusing on demographics in government identification forms such as driver's licenses, fingerprint metadata such a moisture and skin temperature, and face image compliance to an ISO best practice standard. Error was quantified from the first visit and baseline test administrator error rates were measured. Additional training, …


Implementation And Model To Model Intercomparison Of 12 Heat Stress Metrics, Jonathan Robert Buzan Jan 2013

Implementation And Model To Model Intercomparison Of 12 Heat Stress Metrics, Jonathan Robert Buzan

Open Access Theses

Earth system models simulate the dynamics of the most complex systems on our planet with some success. Despite the overwhelming sophistication of these models, which include dynamical interactions of ocean, atmosphere, vegetation, ice, and land-surface properties, they fail to include the most important element. People. Humans are also a complex physical-biological system and coupling of human physiology within an Earth Systems Modeling framework is challenging. This thesis presents results that tackle one particular component of human physiological climate interaction--a representation of heat stress on human physiology. Twelve different metrics were implemented and analyzed. These metrics represent a variety of philosophical …


Callovian (Upper Middle Jurassic) Magnetostratigraphy: A Composite Polarity Pattern From France, Britain And Germany, And Its Correlation To The Pacific Marine Magnetic Anomaly Model, Rachel Anne Gipe Jan 2013

Callovian (Upper Middle Jurassic) Magnetostratigraphy: A Composite Polarity Pattern From France, Britain And Germany, And Its Correlation To The Pacific Marine Magnetic Anomaly Model, Rachel Anne Gipe

Open Access Theses

Callovian strata from sixteen exposures across western Europe produced a nearly continuous composite geomagnetic polarity reference sequence spanning the latest Bathonian (Clydoniceras discus Zone) through the entire Callovian and into the earliest Oxfordian (Quenstedtoceras mariae zone). This sequence is compiled from multi-section sequences from France and England, a section in southern Germany, and a section on the Isle of Skye (Scotland). These sections are calibrated with ammonite biostratigraphy, brachiopod associations and sequence stratigraphy. Over 400 oriented core samples were subjected to progressive thermal demagnetization and filtered according to magnetic behavior; the highest quality suite produced mean paleopoles of 67.3°N, 174.8°E …


The Design And Synthesis Of Peptidomimetic Serine-Based Prodrugs As 14-3-3 Inhibitors, Eric Drake Jones Jan 2013

The Design And Synthesis Of Peptidomimetic Serine-Based Prodrugs As 14-3-3 Inhibitors, Eric Drake Jones

Open Access Theses

Jones, Eric D. Masters of Science, Purdue University, October 2013. THE DESIGN AND SYNTHESIS OF PEPTIDOMEMETIC SERINE-BASED PRODRUGS AS 14-3-3 INHIBITORS. Major Professor: Richard Borch

This work describes the design and synthesis of peptidomimetics for the inhibition of the protein-protein interactions (PPI) with 14-3-3. This protein is a promiscuous binder of other proteins with a variety of key functions such as the regulation of proapoptotic proteins (e.g. FOXO, BAD), suppression of tumor growth, and sensitizing cells to other drugs. The promiscuous binding is the result of PPIs being shallow binding sites which accept many proteins and modify their activity. Compounds …


Value Centric Approaches To The Design, Operations And Maintenance Of Wind Turbines, Madhur Aravind Khadabadi Jan 2013

Value Centric Approaches To The Design, Operations And Maintenance Of Wind Turbines, Madhur Aravind Khadabadi

Open Access Theses

Wind turbine maintenance is emerging as an unexpectedly high component of turbine operating cost, and there is an increasing interest in managing this cost. This thesis presents an alternative view of maintenance as a value-driver, and develops an optimization algorithm to evaluate the value delivered by different maintenance techniques. I view maintenance as an operation that moves the turbine to an improved state in which it can generate more power and, thus, earn more revenue. To implement this approach, I model the stochastic deterioration of the turbine in two dimensions: the deterioration rate, and the extent of deterioration, and then …


Distributed Digital Forensics On Pre-Existing Internal Networks, Jeremiah Jens Nielsen Jan 2013

Distributed Digital Forensics On Pre-Existing Internal Networks, Jeremiah Jens Nielsen

Open Access Theses

Today's large datasets are a major hindrance on digital investigations and have led to a substantial backlog of media that must be examined. While this media sits idle, its relevant investigation must sit idle inducing investigative time lag. This study created a client/server application architecture that operated on an existing pool of internally networked Windows 7 machines. This distributed digital forensic approach helps to address scalability concerns with other approaches while also being financially feasible. Text search runtimes and match counts were evaluated using several scenarios including a 100 GB image with prefabricated data. When compared to FTK 4.1, a …


Sustainable Systems Thinking In Communication Design Education, Yvette M. Perullo Jan 2013

Sustainable Systems Thinking In Communication Design Education, Yvette M. Perullo

Open Access Theses

Design ingenuity and sustainability can, and should, work together. Designers have an ethical responsibility to provide ideas that do no harm, and better yet, create positive solutions that nourish the environment, social and cultural structures, and the economy. This approach, referred to as sustainable systems thinking--in contrast to more common design approaches--looks at a problem as an integrated component of an entire network. Sustainable systems thinking helps designers, clients, and consumers to consider who or what is connected to the design outcome, where the project will have positive and negative ecological, financial, cultural or social impacts, and make the entire …


Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker Jan 2013

Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker

Open Access Theses

Backwater habitats of large rivers provide habitat for aquatic biota and influence important predator-prey interactions in fishes and other aquatic organisms. However, these areas often exhibit turbid conditions and lack habitat complexity. Restoration of lentic habitats through direct habitat manipulations has shown success in prior efforts, but these methods have not been tested in backwater habitats of large rivers. I attempted to create habitat in an Ohio River embayment by establishing founder colonies of aquatic macrophytes coupled with the placement of underwater gravel beds. I also evaluated the effects of total suspended solids (TSS) on overwintering structures of American Pondweed …


Pickering Stabilization Of Oil-Water Interfaces By Heated B-Lactoglobulin/Pectin Particles, Laura Kathryn Zimmerer Jan 2013

Pickering Stabilization Of Oil-Water Interfaces By Heated B-Lactoglobulin/Pectin Particles, Laura Kathryn Zimmerer

Open Access Theses

The use of natural biopolymer particles as Pickering stabilizers for oil-in-water emulsions was investigated. B-lactoglobulin microgels and B-lactoglobulin/pectin complexes were created by heating appropriate biopolymer solutions at pH 5.8 and 4.75, respectively. Resultant particles exhibited spherical morphology with diameters of 100-300 nm and possessed significant negative surface charge. Particles were first homogenized with 1% corn oil at 0.05%, 0.1% or 0.25% (wt/ wt) particle concentrations. All emulsions appeared stable over seven days with only a thin, creamed ring forming after several hours. Corn oil emulsions were most stable with 0.25% heated complexes, with volume-weighted mean droplet diameter remaining around 480 …


Improving Model Performance For Invasive Plant Species Distribution Using Global-Scale Presence-Only Data: Parameterization And Data Quality, Feng Yu Jan 2013

Improving Model Performance For Invasive Plant Species Distribution Using Global-Scale Presence-Only Data: Parameterization And Data Quality, Feng Yu

Open Access Theses

Invasive species have significant ecological and economic impacts. To control species' invasion, risk assessment provides the most essential information for identification and evaluation of the potential risk of the invasive species, especially in their early invasion stages. Species distribution models (SDMs) is the foundation for risk assessment, in terms of both the practical and theoretical interest in our understanding of species invasion process. SDMs contribute to the proactive invasion management and the test of ecological or biogeographical hypotheses about species distributions in relation to their environment.

However, modeling of invasive species at large spatial scale (i.e., cross-continental) is rarely discussed. …


Quantum Computing With Steady State Spin Currents, Brian Matthew Sutton Jan 2013

Quantum Computing With Steady State Spin Currents, Brian Matthew Sutton

Open Access Theses

Many approaches to quantum computing use spatially confined qubits in the presence of dynamic fields to perform computation. These approaches are contrasted with proposals using mobile qubits in the presence of static fields. In this thesis, steady state quantum computing using mobile electrons is explored using numerical modeling. Firstly, a foundational introduction to the case of spatially confined qubits embodied via quantum dots is provided. A collection of universal gates implemented with dynamic fields is described using simulations. These gates are combined to implement a five-qubit Grover search to provide further insight on the time-dependent field approach. Secondly, the quantum …


A Comparative Analysis Of Open Source Storage Area Networks With Esxi 5.1, Robert M. Trinkle Jan 2013

A Comparative Analysis Of Open Source Storage Area Networks With Esxi 5.1, Robert M. Trinkle

Open Access Theses

Storage Area Networks have increased in popularity with the advancement of virtualization technologies. SANs consist of a central repository of hard disks allowing multiple clients to access and share data over a computer network. In recent years, multiple commercial and open source SAN technologies have been introduced to the market. Unlike commercial products, the open source SAN technologies lack formal documentation and research making implementation best practices scarce. This research analyzed the performance of different SAN architectures and implementation strategies. In addition, this paper expands upon previous research by using current hardware and software technologies. The test results of prominent …


Accurate Prediction Of Spectral Phonon Relaxation Time And Thermal Conductivity Of Intrinsic And Perturbed Materials, Tianli Feng Jan 2013

Accurate Prediction Of Spectral Phonon Relaxation Time And Thermal Conductivity Of Intrinsic And Perturbed Materials, Tianli Feng

Open Access Theses

The prediction of spectral phonon relaxation time, mean-free-path, and thermal conductivity can provide significant insights into the thermal conductivity of bulk and nanomaterials, which are important for thermal management and thermoelectric applications. We perform frequency-domain normal mode analysis (NMA) on pure bulk argon and pure bulk germanium. Spectral phonon properties, including the phonon dispersion, relaxation time, mean free path, and thermal conductivity of argon and germanium at different temperatures have been calculated. We find the dependence of phonon relaxation time τ on frequency ω and temperature T vary from ~ω-1.3 to ~ω-1.8 and ~T-0.8 to ~T-1.8 …


Calculated Vibrational Properties Of Ubisemiquinones, Hari P. Lamichhane, Gary Hastings Jan 2013

Calculated Vibrational Properties Of Ubisemiquinones, Hari P. Lamichhane, Gary Hastings

Physics and Astronomy Faculty Publications

Density functional theory has been used to calculate harmonic normal mode vibrational frequencies for unlabeled and isotopelabeled ubisemiquinones in both the gas phase and in several solvents. It is shown that four methoxy group conformations are likely to be present in solution at room temperature. Boltzmann weighted infrared and Raman spectra for the four conformers were calculated, and composite spectra that are the sum of the Boltzmann weighted spectra were produced. These composite spectra were compared to experimental FTIR and resonance Raman spectra, and it is shown that the calculated band frequencies, relative band intensities, and 13C and 18 …


Conformational Plasticity Of An Enzyme During Catalysis: Intricate Coupling Between Cyclophilin A Dynamics And Substrate Turnover, Lauren C. Mcgowan, Donald Hamelberg Jan 2013

Conformational Plasticity Of An Enzyme During Catalysis: Intricate Coupling Between Cyclophilin A Dynamics And Substrate Turnover, Lauren C. Mcgowan, Donald Hamelberg

Chemistry Faculty Publications

Enzyme catalysis is central to almost all biochemical processes, speeding up rates of reactions to biological relevant timescales. Enzymes make use of a large ensemble of conformations in recognizing their substrates and stabilizing the transition states, due to the inherent dynamical nature of biomolecules. The exact role of these diverse enzyme conformations and the interplay between enzyme conformational dynamics and catalysis is, according to the literature, not well understood. Here, we use molecular dynamics simulations to study human cyclophilin A (CypA), in order to understand the role of enzyme motions in the catalytic mechanism and recognition. Cyclophilin A is a …


Adaptive And Sequential Methods For Clinical Trials, Yichuan Zhao, Zhengjia Chen, Xuelin Huang, Mourad Tighiouart Jan 2013

Adaptive And Sequential Methods For Clinical Trials, Yichuan Zhao, Zhengjia Chen, Xuelin Huang, Mourad Tighiouart

Mathematics and Statistics Faculty Publications

This special issue describes state-of-the-art statistical research in adaptive and sequential methods and the application of such methods in clinical trials. It provides 1 review article and 5 research articles contributed by some of the leading experts in this field. The review article gives a comprehensive overview of the outstanding methodology in the current literature that is related to adaptive and sequential clinical trials, while each of the 5 research articles addresses specific critical issues in contemporary clinical trials, as summarized below.


Abundance Patterns In The Spiral Galaxy Messier 33, Melissa A. Siemer, Ravi Sankrit Jan 2013

Abundance Patterns In The Spiral Galaxy Messier 33, Melissa A. Siemer, Ravi Sankrit

STAR Program Research Presentations

Messier 33 (M33) is a spiral disk galaxy, similar to our galaxy, approximately 3 million light-years from Earth. Because of its proximity to Earth and face-on viewing angle, it is easy to see individual objects. Consequently, M33 is in an ideal position for obtaining data on elemental abundances. By studying M33, we learn how galaxies like our own form and change over time.

We use published optical spectroscopic data, obtained and assembled from online sources, to map the abundances of various elements (Helium, Nitrogen, Oxygen, Neon, Argon, Sulfur) in the planetary nebula and HII region populations of M33. We classify …


Seeing Through A Cloudy Glass: Putting Limits On Planetary Nebulae Abundances Using Photoionization Modeling., Peter R. Sullivan, Ravi Sankrit Jan 2013

Seeing Through A Cloudy Glass: Putting Limits On Planetary Nebulae Abundances Using Photoionization Modeling., Peter R. Sullivan, Ravi Sankrit

STAR Program Research Presentations

Planetary nebulae (PNe) form around low to intermediate mass stars transitioning from the giant branch to white dwarf phase. The outer layer of the star is ejected during the transition and this gas, ionized by the central star, emits a line-spectrum. This spectrum traces the chemical abundances that were characteristic of the interstellar medium in which the star formed (e.g. oxygen) as well as of the elements created by these progenitor stars (e.g. nitrogen) aiding our understanding of chemical evolution of galaxies. In this project, we use modeling of the emission lines of PNe to determine the accuracy of direct …


Using Stable Isotope Analysis Of Zooplankton To Document Trophic And Biogeochemical Changes In The San Francisco Estuary, Steven C. Westbrook, Julien Moderan Jan 2013

Using Stable Isotope Analysis Of Zooplankton To Document Trophic And Biogeochemical Changes In The San Francisco Estuary, Steven C. Westbrook, Julien Moderan

STAR Program Research Presentations

Zooplankton represent a vital link between phytoplankton and fish, like the endangered Delta Smelt. Human interferences (nitrates from waste water, flow alteration, invasive species introduction…) have altered the structure of the San Francisco Estuary (SFE) ecosystem. We use stable isotope analysis to improve our knowledge of the planktonic food web in the SFE and gain insights into its evolution over the past decades. We use the ratios of certain isotopes (Nitrogen, Carbon, Sulfur, etc.) in different species of zooplankton to tell us what it is feeding on as well as the trophic level it feeds in. My research focused on …


Chemical Compatibility Study Of Anti-Corrosive Materials For Stratospheric Observatory For Infrared Astronomy (Sofia), Belyn Nicole Grant, Zaheer Ali, Greg Perryman, Stefan Teufel, Brian Eney Jan 2013

Chemical Compatibility Study Of Anti-Corrosive Materials For Stratospheric Observatory For Infrared Astronomy (Sofia), Belyn Nicole Grant, Zaheer Ali, Greg Perryman, Stefan Teufel, Brian Eney

STAR Program Research Presentations

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a telescope designed to capture infrared light from deep space, mounted in a highly modified Boeing 747 SP. Portions of the aircraft interior are showing signs of corrosion, and need to be coated with a material that will prevent further corrosion. Up to date, current anti-corrosive materials commonly used on aircrafts are incompatible with the very thin aluminum surface of the telescope mirrors. The purpose of our study is to find an effective corrosion preventive material with low outgassing properties.


Femtosecond Filament Interaction As A Probe For Molecular Alignment, Erik Mckee Jan 2013

Femtosecond Filament Interaction As A Probe For Molecular Alignment, Erik Mckee

Electronic Theses and Dissertations

Femtosecond laser filamentation is a highly nonlinear propagation mode. When a laser pulse propagates with a peak power exceeding a critical value Pcr (5 GW at 800 nm in air), the Kerr effect tends to collapse the beam until the intensity is high enough to ionize the medium, giving rise to plasma defocusing. A dynamic competition between these two effects takes place leaving a thin and weakly ionized plasma channel in the trail of the pulse. When an ultrafast laser pulse interacts with molecules, it will align them, spinning them about their axis of polarization. As the quantum rotational wave …


On The Capillary Electrophoresis Of Monohydroxy Metabolites Of Polycyclic Aromatic Hydrocarbons And Its Application To The Analysis Of Biological Matrices, Gaston Knobel Jan 2013

On The Capillary Electrophoresis Of Monohydroxy Metabolites Of Polycyclic Aromatic Hydrocarbons And Its Application To The Analysis Of Biological Matrices, Gaston Knobel

Electronic Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAH) are a class of environmental pollutants consisting of a minimum of two fused aromatics rings originating from the incomplete combustion of organic matter and/or anthropogenic sources. Numerous possible anthropogenic and natural sources make the presence of PAH ubiquitous in the environment. The carcinogenic nature of some PAH and their ubiquitous presence makes their chemical analysis a topic of environmental and toxicological importance. Although environmental monitoring of PAH is an important step to prevent exposure to contaminated sites, it provides little information on the actual uptake and subsequent risks. Parent PAH are relatively inert and need metabolic …


Climate Change Impacts On Rainfed Corn Production In Malawi, Kondwani Msowoya Jan 2013

Climate Change Impacts On Rainfed Corn Production In Malawi, Kondwani Msowoya

Electronic Theses and Dissertations

Agriculture is the mainstay of the economy in Malawi and accounts for 40% of the Gross Domestic Product (GDP) and 90% of the export revenues. Corn (maize) is the major cereal crop grown as staple food under rainfed conditions, covers over 92% of the total agricultural area, and contributes 54% of the caloric intake. Corn production is the principle occupation and major source of income for over 85% of the total population in Malawi. Issues of hunger and food insecurity for the entire nation are associated with corn scarcity and low production. Global warming is expected to cause climate change …