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2015

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Articles 11521 - 11550 of 11621

Full-Text Articles in Physical Sciences and Mathematics

Factors Influencing Mottled Duck Nest Success On The Atchafalaya River Delta, Brendan Caillouet Jan 2015

Factors Influencing Mottled Duck Nest Success On The Atchafalaya River Delta, Brendan Caillouet

LSU Master's Theses

The Atchafalaya River Delta system along with the Wax Lake Outlet Delta and the Mississippi River Delta are the only three areas in Louisiana where land is being gained. Beneficial use of dredge spoil from shipping channel maintenance is used on the Atchafalaya River Delta to supplement natural accretion. These dredge spoil islands have the ability to provide valuable nesting habitat for a variety of waterbirds, including Mottled Ducks. Previous studies on these islands reported mammalian predation to be a significant cause of nest failure for Mottled Ducks. I tested the hypothesis that predator reduction through trapping would increase Mottled …


Twentieth Century Droughts And Agriculture: Examples From Impacts On Soybean Production In Kentucky, Usa, Rezaul Mahmood Jan 2015

Twentieth Century Droughts And Agriculture: Examples From Impacts On Soybean Production In Kentucky, Usa, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.


Structural Requirements For Ribosome-Dependent Gtpase Activity And Binding, Markus A. Carlson Jan 2015

Structural Requirements For Ribosome-Dependent Gtpase Activity And Binding, Markus A. Carlson

WWU Graduate School Collection

The two billion years of evolution since the divergence of prokaryotes and eukaryotes has left earth with very few molecules conserved across these two domains of life. One such molecule, the ribosome, is an enormous ribonucleoprotein responsible for translation, the process of converting the information contained within an organism’s genetic code into functional proteins. Translation is facilitated by a number of other proteins, termed translation factors, required to catalyze the synthesis of these proteins. A large number of antibiotics prescribed today target either the ribosome or translation factors, and with increasing antibiotic resistance being found in infectious bacteria there is …


Differential Incision And Uplift Of The Yakima River Terraces, Adrian M. Bender Jan 2015

Differential Incision And Uplift Of The Yakima River Terraces, Adrian M. Bender

WWU Graduate School Collection

The Yakima fold belt comprises fault-related folds deforming Miocene basalts and younger deposits of the Columbia Plateau in central Washington State. Geodesy implies ~2 mm/yr of modern, NNE-directed regional shortening; however the distribution of Quaternary deformation among individual structures remains unclear. South of Ellensburg, Washington, the Yakima River cuts a ~600-m deep canyon across several of the folds, preserving flights of strath terraces that record the progressive incision. Graded alluvial basins at the head and mouth of the canyon imply that terrace incision also records differential rock uplift. We integrate lidar analysis, field observations, and cosmogenic burial dating of eight …


Marine Microzooplankton Are Indirectly Affected By Ocean Acidification Through Direct Effects On Their Phytoplankton Prey, Kasey Kendall Jan 2015

Marine Microzooplankton Are Indirectly Affected By Ocean Acidification Through Direct Effects On Their Phytoplankton Prey, Kasey Kendall

WWU Graduate School Collection

To date few studies have explored indirect effects of OA on microzooplankton. Microzooplankton grazing behavior is acutely sensitive to prey cell size, physiology, and nutritional state, which may all be influenced by OA in phytoplankton. Therefore, microzooplankton may be indirectly affected by OA through their prey. Due to undersaturation of CO2 for the carboxylating enzyme, RuBisCO, increasing availability of CO2 through acidification could affect algal cellular processes, physiological states, and the nutritional value for their primary consumers. In this study I tested for indirect effects of OA on three microzooplankton species, representing two ecologically significant functional groups of …


Fluorescence Imaging Of Analyte Profiles In An Inductively Coupled Plasma With Laser Ablation As A Sample Introduction Source, Lance Moses Jan 2015

Fluorescence Imaging Of Analyte Profiles In An Inductively Coupled Plasma With Laser Ablation As A Sample Introduction Source, Lance Moses

Theses and Dissertations

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has risen to among the top tier techniques for the direct analysis of solid samples. However, significant problems remain that must be solved to achieve the full analytical potential of LA-ICP-MS. Inefficient conversion of aerosol to ions within the ICP or transmission through the MS interface may decrease precision, sensitivity, and/or accuracy. Although fundamental mechanisms that govern ion production and transmission have been studied extensively in solution-nebulization (SN) ICP-MS instruments, significant gaps in our understanding remain. Furthermore, it is unclear to what extent differences between the aerosols generated during SN and LA …


Frontier: A Framework For Extracting And Organizing Biographical Facts In Historical Documents, Joseph Park Jan 2015

Frontier: A Framework For Extracting And Organizing Biographical Facts In Historical Documents, Joseph Park

Theses and Dissertations

The tasks of entity recognition through ontological commitment, fact extraction and organization with respect to a target schema, and entity deduplication have all been examined in recent years, and systems exist that can perform each individual task. A framework combining all these tasks, however, is still needed to accomplish the goal of automatically extracting and organizing biographical facts about persons found in historical documents into disambiguated entity records. We introduce FROntIER (Fact Recognizer for Ontologies with Inference and Entity Resolution) as the framework to recognize and extract facts using an ontology and organize facts of interest through inferring implicit facts …


Electrospun Titanium Dioxide And Silicon Composite Nanofibers For Advanced Lithium Ion Batteries, Kathleen Mccormac Jan 2015

Electrospun Titanium Dioxide And Silicon Composite Nanofibers For Advanced Lithium Ion Batteries, Kathleen Mccormac

Electronic Theses and Dissertations

A unique electrospinning method was implemented to fabricate composite nanofibers for lithium ion battery applications. The composite nanofibers were made of amorphous carbon, rutile phase TiO2, and cubic phase Si nanoparticles. Sulfur was utilized as a template to form void structures within the TiO2 nanofiber matrix. This provides the desired space for the Si expansion during the lithiation process. Phase, structure, composition, and morphology of the nanofibers were characterized using Raman spectroscopy, SEM, EDS, TGA, and powder XRD. Carbonized TiO2 nanofibers showed a low but stable specific capacity. Si Nanoparticles demonstrated an initially high but fast …


A Survey Of Mathematical Models Of Dengue Fever, Iurii Bakach Jan 2015

A Survey Of Mathematical Models Of Dengue Fever, Iurii Bakach

Electronic Theses and Dissertations

In this paper, we compare and contrast five models of Dengue fever. We evaluate each model using different scenarios and identify the strenghts and wecknesses of each of the model


Improved Full-Newton-Step Infeasible Interior-Point Method For Linear Complementarity Problems, Mustafa Ozen Jan 2015

Improved Full-Newton-Step Infeasible Interior-Point Method For Linear Complementarity Problems, Mustafa Ozen

Electronic Theses and Dissertations

In this thesis, we present an improved version of Infeasible Interior-Point Method (IIPM) for monotone Linear Complementarity Problem (LCP). One of the most important advantages of this version in compare to old version is that it only requires feasibility steps. In the earlier version, each iteration consisted of one feasibility step and some centering steps (at most three in practice). The improved version guarantees that after one feasibility step, the new iterated point is feasible and close enough to central path. Thus, the centering steps are eliminated. This improvement is based on the Lemma(Roos, 2015). Thanks to this lemma, proximity …


The Sensitivity Of A Test Based On Spearman's Rho In Cross-Correlation Change Point Problems, Congjian Liu Jan 2015

The Sensitivity Of A Test Based On Spearman's Rho In Cross-Correlation Change Point Problems, Congjian Liu

Electronic Theses and Dissertations

In change point problems, there are three main questions that researchers are interested in. First of all, is there a change point or not? Second, when does the change point occur in a time series? Third, how quickly can we detect the change point? In this thesis, we first explain what a change point is, and what a cross-correlation is. We then discuss prior research in this area. Then we discuss and examine a test based on Spearman's rho, introduced by Wied and Dehling (2011), which tests the null hypothesis of no change point, and compare the change point we …


Testing Data Vault-Based Data Warehouse, Connard N. Williams Jan 2015

Testing Data Vault-Based Data Warehouse, Connard N. Williams

Electronic Theses and Dissertations

Data warehouse (DW) projects are undertakings that require integration of disparate sources of data, a well-defined mapping of the source data to the reconciled data, and effective Extract, Transform, and Load (ETL) processes. Owing to the complexity of data warehouse projects, great emphasis must be placed on an agile-based approach with properly developed and executed test plans throughout the various stages of designing, developing, and implementing the data warehouse to mitigate against budget overruns, missed deadlines, low customer satisfaction, and outright project failures. Yet, there are often attempts to test the data warehouse exactly like traditional back-end databases and legacy …


Effects Of Heavy Metals On Benthic Macroinvertebrates In The Cordillera Blanca, Peru, George L (George Livingston) Burgess Jan 2015

Effects Of Heavy Metals On Benthic Macroinvertebrates In The Cordillera Blanca, Peru, George L (George Livingston) Burgess

WWU Graduate School Collection

Glacial retreat as a result of global climate change is causing ongoing alterations in the hydrogeochemistry of streams in the glacial foreland of the Cordillera Blanca mountain range in Ancash, Peru. Changes in water chemistry include increased concentrations of toxic metals and decreased pH, which have the potential to affect the structure of benthic macroinvertebrate communities in impacted streams. This study measured physical-chemical water quality parameters, metal concentrations, and macroinvertebrate abundances at 29 sample reaches throughout seven valleys located in Huascaran National Park. The relationships of invertebrate abundances and metrics of community structure to water quality parameters, including metal concentrations, …


Non-Covalent Ineteractions Of Trimethylamine N-Oxide (Tmao) And Urea In Water, John Prather Jan 2015

Non-Covalent Ineteractions Of Trimethylamine N-Oxide (Tmao) And Urea In Water, John Prather

Honors Theses

TMAO and urea are important osmolytes. Osmolytes help maintain cell volume with their presence inside and outside cells. Urea is used by kidney cells to neutralize strong osmotic gradients caused by excretion of hypertonic waste. Although urea is for volume- maintaining purposes, it is also known to be a strong denaturant of cellular proteins. The method by which urea destabilizes folded proteins is a debated topic. There is evidence that urea binds directly to amino acid side chains to make protein folding less thermodynamically favored. It has also been suggested that urea acts indirectly to denature proteins by destabilizing the …


Wind Energy Harvesting Utilizing Biaxially Oriented Piezoelectric Polyvinylidenefluoride Film, Matthew Kennedy Jan 2015

Wind Energy Harvesting Utilizing Biaxially Oriented Piezoelectric Polyvinylidenefluoride Film, Matthew Kennedy

Honors Theses

With the growing concern over fossil fuels as a finite source of fuel and as a hazard to the environment, society has developed a growing interest in the use of renewable energy. Advancements in solar, nuclear, geothermal, wind, and vibrational energy harvesting, to name a few, have made the concept of using renewables as a main source of energy more feasible. The research and experimentation conducted for this thesis focused on analyzing the practicality of the future implementation of Biaxially Oriented Piezoelectric Polyvinylidenefluoride in the wind energy harvesting industry. The experiment consisted of data collection and analysis of power output …


Para-Interface: A Novel Interface For Para-Aeh Software Suite, Michael Ginn Jan 2015

Para-Interface: A Novel Interface For Para-Aeh Software Suite, Michael Ginn

Honors Theses

Para-AEH is a software suite designed to the Asymptotic Expansion Homogenization method. This method is commonly used to model structures by using differential equations to represent larger structure from a smaller structure input. In order to facilitate the University of Mississippi's Department of Mechanical Engineering's research purposes the software needed to be installed. A novel interface was designed to remove the overhead of interacting with the software on a command line based level. The software allows the management of users that can access the software and jobs that package several commands together for asynchronous execution without manual intervention.


Effect Of Biochar And Activated Carbon Amendments On Gaseous Mercury Emissions Of Soil And Mercury Methylation Rates In Sediment, Ryan Sessums Jan 2015

Effect Of Biochar And Activated Carbon Amendments On Gaseous Mercury Emissions Of Soil And Mercury Methylation Rates In Sediment, Ryan Sessums

Honors Theses

Mercury is a pervasive global contaminant with a complex biogeochemical cycle. In this biogeochemical cycle, methylmercury (MeHg+) tends to biomagnify and concentrate in fish and seafood consumed by humans. This study examines the effect of sorbent amendments on both the mercury emission from soils and the methylation rates of mercury in sediments, both of which are believed to be major contributors to the global cycle. Biochar and activated carbon were used to treat soils and sediments to explore their effects. It was found that biochar and activated carbon reduced gaseous mercury emission by 25% and 49%, respectively. Methylation rates in …


The Effect Of Polyamines On I-Motif Thermal Stablity, Shelby Claire Liddell Jan 2015

The Effect Of Polyamines On I-Motif Thermal Stablity, Shelby Claire Liddell

Honors Theses

Polyamines are present inside cells at varying concentrations anywhere between 10 mM and 60 mM, and because of their molecular structure they contribute a positive charge to the interior of the cell. There has been previous evidence that the concentrations of polyamines have an effect on the stability of the DNA strands, which can affect the cellular processes. The particular DNA conformation studied is the i-motif, which is formed by intermolecular folding in cytosine rich strands. The i-motif studied is C20T, which is found in the promoter region of the oncogene, c-myc. Stabilization of c-myc can have an effect on …


An Investigation Of Protein-Dna Binding Characteristics By Fluorescence Anisotropy, Danna Nobile Jan 2015

An Investigation Of Protein-Dna Binding Characteristics By Fluorescence Anisotropy, Danna Nobile

Honors Theses

Recent studies have illustrated the presence of several secondary, non-B DNA structures that are associated with the promoter regions of several oncogenes, such as the intensely studied MYC gene. Two such secondary structures, G-quadruplexes and i-Motifs, have become topics of interest due to their prevalence within oncogenic promoters and their potential accessibility for future drug targeting due to their globular natures. Though fairly extensive research has been conducted to understand different factors affecting G-quadruplex formation and stability, similar studies for i-Motifs, particularly related to thermodynamics, are still evolving. One factor known to contribute to the additional energy required for duplex …


Integrated Human Health And Ecological Risk Assessment For The South River, Virginia: A Bayesian Approach, Meagan J. Harris Jan 2015

Integrated Human Health And Ecological Risk Assessment For The South River, Virginia: A Bayesian Approach, Meagan J. Harris

WWU Graduate School Collection

Regional scale risk assessments can be used to determine the likelihood of effects from multiple stressors on ecological or human endpoints at multiple scales. The Relative Risk Model framework can incorporate ecosystem services as endpoints in this multiple stressor- multiple endpoint approach. Through this research, I aimed to demonstrate an approach to integrating ERA and HHRA that could be applied to assess risk to human health and ecosystem services using the South River, VA as a case study. I applied the Relative Risk Model with Bayesian networks (BN-RRM) to an integrated assessment of four ecosystem services of the South River, …


Profiling Sortase Substrate Specificity Using Peptide Libraries, Keyvan Dastkhosh Nikghalb Jan 2015

Profiling Sortase Substrate Specificity Using Peptide Libraries, Keyvan Dastkhosh Nikghalb

WWU Graduate School Collection

The use of enzymes for protein modification chemistry has gained traction in recent years due to the remarkable site-selectivity that enzymes afford. Among enzymes reported for this purpose, sortase A from Staphylococcus aureus (SrtAStaph) has garnered significant attention because of its selectivity, and its ability to install a wide range of non-natural modifications. In addition to SrtAStaph, it is now appreciated that sortase homologs exist in many bacterial strains, each with the potential to serve as a new catalyst for protein engineering. However, the majority of these enzymes has not been studied biochemically, and in order to utilize these enzymes …


Structural Studies Of Blood Coagulation Factor Viii In Protein Complexes, Michelle E. Wuerth Jan 2015

Structural Studies Of Blood Coagulation Factor Viii In Protein Complexes, Michelle E. Wuerth

WWU Graduate School Collection

A deficiency in blood coagulation factor VIII (fVIII) is responsible for the inherited bleeding disorder hemophilia A, which affects approximately 1 in 5000 males. The development of inhibitory antibodies is a significant issue faced by hemophilia A patients receiving therapeutic infusions of fVIII. The C-terminal C2 domain of fVIII has been shown to be highly immunogenic and the site of binding for numerous antibodies of both the classical and non-classical classifications. A detailed understanding of the structural components involved in C2-antibody binding interactions is vital for the development of improved therapeutics for hemophilia patients. Here we present the structure of …


Ocean Acidification Affects Larval Swimming In Ostrea Lurida But Not Crassostrea Gigas, Shannon Buckham Jan 2015

Ocean Acidification Affects Larval Swimming In Ostrea Lurida But Not Crassostrea Gigas, Shannon Buckham

WWU Graduate School Collection

The effects of ocean acidification (OA), which results from increased CO2 emissions, are of particular concern for calcifying marine organisms. In marine invertebrates, the larval stages are generally considered the most vulnerable to the effects of OA and many recent studies show negative impacts of OA on early developmental stages of calcifying marine invertebrates. I studied the impact of OA on larval swimming performance and behavior in the Pacific oyster, Crassostrea gigas, and the Olympia oyster, Ostrea lurida. Swimming studies can be used to understand how short-term performance and behavior changes may affect the long-term success of …


Paleomagnetic Determination Of Vertical-Axis Block Rotation And Magnetostratigraphy In The Mecca Hills And Coachella Valley, California, Cassidy W. (Cassidy Wade) Dimitroff Jan 2015

Paleomagnetic Determination Of Vertical-Axis Block Rotation And Magnetostratigraphy In The Mecca Hills And Coachella Valley, California, Cassidy W. (Cassidy Wade) Dimitroff

WWU Graduate School Collection

Our ongoing work on the paleomagnetism and magnetostratigraphy in the Coachella Valley has provided an improved understanding of the timing and spatial variations of sediment accumulation and deformation during evolution of plate-boundary fault zones. Here, we report updated results from the Palm Spring Formation of the Mecca Hills, and new paleomagnetic data from Pleistocene conglomeratic sandstone in Desert Hot Springs and the Plio-Pleistocene San Timoteo Formation from Live Oak Canyon.

From the Mecca Hills, new data were obtained-112 samples from 29 sites. The majority of the paleomagnetic results yielded well-defined components of magnetization, which allowed us to identify seven well …


Law And The Art Of Modeling: Are Models Facts?, Rebecca Haw Allensworth Jan 2015

Law And The Art Of Modeling: Are Models Facts?, Rebecca Haw Allensworth

Vanderbilt Law School Faculty Publications

In 2013, the Supreme Court made the offhand comment that empirical models and their estimations or predictions are not 'findings of fact" deserving of deference on appeal. The four Justices writing in dissent disagreed, insisting that an assessment of how a model works and its ability to measure what it claims to measure are precisely the kinds of factual findings that the Court, absent clear error cannot disturb. Neither side elaborated on the controversy or defended its position doctrinally or normatively. That the highest Court could split 5-4 on such a crucial issue without even mentioning the stakes or the …


On Representations Of Semigroups Having Hypercube-Like Cayley Graphs, Cody Cassiday, G. Stacey Staples Jan 2015

On Representations Of Semigroups Having Hypercube-Like Cayley Graphs, Cody Cassiday, G. Stacey Staples

SIUE Faculty Research, Scholarship, and Creative Activity

The $n-dimensional hypercube, or n-cube, is the Cayley graph of the Abelian group Z2n. A number of combinatorially-interesting groups and semigroups arise from modified hypercubes. The inherent combinatorial properties of these groups and semigroups make them useful in a number of contexts, including coding theory, graph theory, stochastic processes, and even quantum mechanics. In this paper, particular groups and semigroups whose Cayley graphs are generalizations of hypercubes are described, and their irreducible representations are characterized. Constructions of faithful representations are also presented for each semigroup. The associated semigroup algebras are realized within the context …


Daily Soil Surface Co2 Flux During Non-Flooded Periods In Flood-Irrigated Rice Rotations, J. M. Motschenbacher, K. R. Brye, M. M. Anders, E. E. Gbur, N. A. Slaton, M. A. Evans-White Jan 2015

Daily Soil Surface Co2 Flux During Non-Flooded Periods In Flood-Irrigated Rice Rotations, J. M. Motschenbacher, K. R. Brye, M. M. Anders, E. E. Gbur, N. A. Slaton, M. A. Evans-White

School of Natural Resources: Faculty Publications

No abstract provided.


Gold(Iii)-Catalyzed Cyclizations To Form Saturated Oxygen Heterocycles, Ryan D. Lyski Jan 2015

Gold(Iii)-Catalyzed Cyclizations To Form Saturated Oxygen Heterocycles, Ryan D. Lyski

WWU Graduate School Collection

Gold catalysis has emerged over the past decade as an important methodology in the construction of organic molecules. Cationic gold complexes are robust, versatile, selective and efficient catalysts that can be used to enhance the electrophilicity of C-C unsaturated bonds. A current area of investigation is the use of gold to activate allylic alcohol/ether moieties for intramolecular SN2’ nucleophilic attack to form oxygen heterocycles. We have discovered that sterically bulky, electron-withdrawing oxygen leaving groups drastically improved reaction efficiency, and bulky leaving groups in combination with substrate substituents enhanced diastereomeric ratios in the oxygen heterocycle products. These reactions proceeded …


Land Use/Land Cover Changes And Regional Climate Over The Loess Plateau During 2001-2009 – Part Ii., Rezaul Mahmood Jan 2015

Land Use/Land Cover Changes And Regional Climate Over The Loess Plateau During 2001-2009 – Part Ii., Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.


Infrared Radiography: Modeling X-Ray Imaging Without Harmful Radiation, Otto Zietz, Elliot E. Mylott, Ralf Widenhorn Jan 2015

Infrared Radiography: Modeling X-Ray Imaging Without Harmful Radiation, Otto Zietz, Elliot E. Mylott, Ralf Widenhorn

Physics Faculty Publications and Presentations

Planar x-ray imaging is a ubiquitous diagnostic tool and is routinely performed to diagnose conditions as varied as bone fractures and pneumonia. The underlying principle is that the varying attenuation coefficients of air, water, tissue, bone, or metal implants within the body result in non-uniform transmission of x-ray radiation. Through the detection of transmitted radiation, the spatial organization and composition of materials in the body can be ascertained. In this paper, we describe an original apparatus that teaches these concepts by utilizing near infrared radiation and an up-converting phosphorescent screen to safely probe the contents of an opaque enclosure.