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2014

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Articles 11761 - 11790 of 12299

Full-Text Articles in Physical Sciences and Mathematics

Effects Of Saltwater Intrusion On Vegetation Dynamics And Nutrient Pools In Low-Salinity Tidal Marshes, Pamunkey River (Virginia, Usa), Lori A. Sutter Jan 2014

Effects Of Saltwater Intrusion On Vegetation Dynamics And Nutrient Pools In Low-Salinity Tidal Marshes, Pamunkey River (Virginia, Usa), Lori A. Sutter

Dissertations, Theses, and Masters Projects

This study investigated vegetation changes in a former tidal freshwater marsh (TFM) to determine the role that salinity intrusion plays in vegetation dynamics. Field observations along a narrow salinity gradient in the Pamunkey River revealed that vegetation is shifting to fewer dominants with increasing salinity. Two remaining dominants, Peltandra virginica and Zizania aquatica (hereafter Peltandra and Zizania, respectively), had variable net CO2 assimilation throughout the growing season. Peltandra net CO2 assimilation declined both over the growing season and in marshes with higher salinity; whereas, Zizania generally increased over the growing season peaking in late summer. The same species' tissue nutrients …


Factors Influencing Year-Class Strength And Growth Of Young-Of-The-Year Summer Flounder (Paralichthyidae: Paralichthys Dentatus), Lauren N. Nys Jan 2014

Factors Influencing Year-Class Strength And Growth Of Young-Of-The-Year Summer Flounder (Paralichthyidae: Paralichthys Dentatus), Lauren N. Nys

Dissertations, Theses, and Masters Projects

No abstract provided.


Contractional Tectonics: Investigations Of Ongoing Construction Of The Himalaya Fold-Thrust Belt And The Trishear Model Of Fault-Propagation Folding, Hongjiao Yu Jan 2014

Contractional Tectonics: Investigations Of Ongoing Construction Of The Himalaya Fold-Thrust Belt And The Trishear Model Of Fault-Propagation Folding, Hongjiao Yu

LSU Doctoral Dissertations

This dissertation focuses on the kinematic evolution of contractional tectonics: the Himalayan fold-thrust belt along the collisional orogenic belts, and growth of the basement-cored monoclines in Colorado Plateau. Ongoing Himalayan growth is generally thought to be dominated by duplexing and/or extrusion processes. Duplexing models highlight accretion of material from the subducting plate to the over-riding orogenic wedge, whereas extrusion models focus on up-dip translation of a block bounded by out-of-sequence faults. Here, a primary outstanding question involves the uncertain relationship of the Berinag thrust and the Tons thrust, structures with displacements of >80 km and >40 km, respectively. The uncertainty …


A Contrast Of Hunter Characteristics And Attitudes Between Random And Convenience Samples In The 2010, 2012, And 2013 Surveys Of Louisiana Waterfowl Hunters, Lucien Jr. Paul Laborde Jan 2014

A Contrast Of Hunter Characteristics And Attitudes Between Random And Convenience Samples In The 2010, 2012, And 2013 Surveys Of Louisiana Waterfowl Hunters, Lucien Jr. Paul Laborde

LSU Doctoral Dissertations

I surveyed random (mail and internet panel surveys) and convenience samples (web surveys) of Louisiana waterfowl hunters following the 2009-2010, 2011-2012, and 2012-2013 seasons. I hypothesized significant differences in effort, success, satisfaction and demographics, but no difference in attitudes, in responses between random and convenience survey methods. I mailed to stratified random samples of 2,500 in 2010, 6,400 in 2012, and 2,500 each for mail and on-line internet panel response in 2013. An identical web survey, hosted each year during the same time period, facilitated open-access response. I received 1,676 usable responses in 2010 (727 mail and 949 web), 2,382 …


On Harmonic Vibrational Frequency Convergence To The Complete Basis Set Limit In Water Dimers And Hydrogen Fluoride Dimers, Amanda Hardwick Jan 2014

On Harmonic Vibrational Frequency Convergence To The Complete Basis Set Limit In Water Dimers And Hydrogen Fluoride Dimers, Amanda Hardwick

Honors Theses

This work focuses on the convergence of harmonic vibrational frequencies in the water dimer (H2O)2 and the hydrogen fluoride dimer (HF)2 to the complete basis set (CBS) limit. It also evaluates the effect of counterpoise (CP) correction procedures and the effect of sequentially removing diffuse functions from specific basis sets on the harmonic vibrational frequencies of these dimers. Computations were run using second-order Møller-Plesset perturbation theory (MP2) with large, flexible correlation consistent basis sets. This research aims to determine if removing diffuse functions can increase the speed of harmonic vibrational frequency computations without sacrificing accuracy. Results indicate that CP-correction procedures …


Investigation Into The Synthesis Of Dodecahydro-3a,9a-Diazaperylene, Andrew Palmer Jan 2014

Investigation Into The Synthesis Of Dodecahydro-3a,9a-Diazaperylene, Andrew Palmer

Honors Theses

Dodecahydro-3a,9a-diazaperylene (DHDAP) may serve as a potential donor for use in a donor-sigma-acceptor complex for unimolecular rectification. In order to use DHDAP as a donor, its synthesis must first be studied and altered in such manners as to add a synthetic handle. Other things of important include increasing the yield and better understanding the mechanism by which DHDAP forms. Numerous experiments were conducted in various manners such as testing various solvents among various temperatures to even adding in extra reagents to push the reaction one way or another. In the end the yield of the synthesis was found to improve …


Raman Spectroscopic And Computational Analysis Of The Effects Of Noncovalent Interactions On Dmso, Ashton T. Nicholson Jan 2014

Raman Spectroscopic And Computational Analysis Of The Effects Of Noncovalent Interactions On Dmso, Ashton T. Nicholson

Honors Theses

Dimethyl sulfoxide (DMSO) is a widely used chemical in synthetic chemistry and also has unique and important biological applications. In the pure liquid, DMSO forms chain like structures of alternating sulfur and oxygen atoms due to its high self-association. However, it is known that DMSO/water mixtures form solutions with unique physical characteristics depending on the mole ratio. For instance, at a 1:2 ratio of DMSO/water a eutectic mixture forms with a freezing point of-70 C. Vibrational spectroscopy allows us to study the effects of noncovalent interactions when water and DMSO interact in solution. Spectral shifts can be analyzed in order …


Anchoring The Potential Energy Surfaces Of Homogenous And Heterogenous Dimers Of Formaldehyde And Thiofomaldehyde, Christina M. Holy Jan 2014

Anchoring The Potential Energy Surfaces Of Homogenous And Heterogenous Dimers Of Formaldehyde And Thiofomaldehyde, Christina M. Holy

Honors Theses

This work characterizes five stationary points of the formaldehyde dimer, (CH2O)2, two of which are minima, seven newly-identified stationary points of the formaldehyde/thioformaldehyde (mixed) dimer, CH2O/CH2S, four of which are minima, and five newly-identified stationary points of the thioformaldehyde dimer, (CH2S)2 , three of which are minima. Full geometry optimizations and corresponding harmonic vibrational frequencies were performed on CH2O and CH2S as well as each of the dimer configurations (Figures 3-5). The computations were carried out with second order Møller-Plesset perturbation theory (MP2), with the heavy-auc-cc-pVTZ (haTZ) basis set. Additionally, thirteen density functional theory methods were employed: B3LYP, B3LYP-D3, B3LYP-D3(BJ), …


Detector Characterization Analysis Of The Initial Laser Interferometer Gravitational-Wave Observatory (Ligo) Using Principal Component Analysis (Pca), Daniel Duddleston Jan 2014

Detector Characterization Analysis Of The Initial Laser Interferometer Gravitational-Wave Observatory (Ligo) Using Principal Component Analysis (Pca), Daniel Duddleston

Honors Theses

The purpose of this thesis is to investigate transient noise events in data from the initial Laser Interferometer Gravitational-Wave Observatory (LIGO) and to test detector characterization software developed by the LIGO Scientific Collaboration (LSC). Detector characterization is the process of identifying and removing noise that corrupts the data stream of the LIGO detectors. This is vital to improving the sensitivity of the LIGO interferometer and increasing the probability of detecting gravitational waves of astrophysical origin. The data analyzed in this thesis were collected in 2010 during the S6 (Enhanced LIGO) science run. Two software tools, PCAT and Omega Scans, were …


Implementation Of A Visualizer For Web Request Data Generated By An Internet Information Services Server, Daniel J. Garrett Jan 2014

Implementation Of A Visualizer For Web Request Data Generated By An Internet Information Services Server, Daniel J. Garrett

Honors Theses

I was tasked by Graham Green at FNC, Inc. to design a web tool that is capable of visualizing log data that is produced by FNC's many servers. These logs contain data that will warn Graham about web pages that are failing, servers that are experiencing heavy loads, and sundry other pieces of information, but the data is pure text, and each server has thousands of logs. A visual tool is needed to display necessary information about the data. Rather than make a graph for each individual purpose that might be needed, I built visualization tools that are customizable for …


The Origins Of An Everyday Behavior: Why Do People Share Meals?, David Lee Jan 2014

The Origins Of An Everyday Behavior: Why Do People Share Meals?, David Lee

Honors Theses

Humans are socially driven creatures that require constant interaction. One way humans have consistently expressed their social nature since prehistory is through sharing meals. Recent studies and literature were examined in order to investigate the roots behind why sharing meals has been the most consistent method of social output. Through careful reading and analysis, reasons behind why people share meals were traced in perspective levels. The biological and molecular aspect explains how humans evolved from prehistoric primates and their similarities associated with food consumption. Genetics and food preferences also play a role by allowing humans to taste food rather than …


Independence Polynomials And Extended Vertex Reduction, Jonathan Broom Jan 2014

Independence Polynomials And Extended Vertex Reduction, Jonathan Broom

Honors Theses

The independence polynomial of a graph is a polynomial whose coefficients number the independent sets of each size in that graph. This paper looks into methods of obtaining these polynomials for certain classes of graphs which prove too large to easily find the polynomial by traditional methods.


The Matrix Method Of Linear Dichroism, Kenna Collums Jan 2014

The Matrix Method Of Linear Dichroism, Kenna Collums

Honors Theses

This thesis discusses linear dichroism, and in particular the matrix method behind the spectroscopic technique. Linear dichroism uses the difference in the absorption of light that is parallel to the orientation axis and the absorption of light that is perpendicular to the orientation axis. From this process, the structure and function of molecules can be studied. The matrix method diagonalizes a Hamiltonian matrix with a unitary matrix. This Hamiltonian matrix is constructed from the transition energies, which are the diagonal elements, and coupling energies, which are off-diagonal elements.


Non-Covalent Interactions, Dative Bonding, And Electron Affinities: A Multi-Method Computational Study Of Boron Tetrahalides, Lance R. Ezell Jan 2014

Non-Covalent Interactions, Dative Bonding, And Electron Affinities: A Multi-Method Computational Study Of Boron Tetrahalides, Lance R. Ezell

Honors Theses

This study focuses on boron tetrahalides of the form BFXClY, where X + Y = 4, using the B3LYP, M06-2X, and MP2 methods with the aug-cc-pVTZ basis set. The various neutral and anionic species were constructed and optimized using the Gaussian 09 software package, and the equilibrium geometries, harmonic vibrational frequencies, and energetics (specifically the electron affinity, vertical attachment and detachment energies, and stability with respect to dissociation) of each system are presented. The anionic species, due to their closed-shell electron configurations, have relatively high symmetry: Td for BF4- and BCl4-, C3v for BF3Cl- and BFCl3-, and C2v for BF2Cl2-. …


Shear Waves In Highly Concentrated Viscoelastic Wormlike Micellar Fluid, Rachel B. Crim Jan 2014

Shear Waves In Highly Concentrated Viscoelastic Wormlike Micellar Fluid, Rachel B. Crim

Honors Theses

Wormlike micellar fluids form by the self-aggregation of surfactant molecules in aqueous solution. These non-Newtonian fluids have been well studied and are used in the oil industry, hydraulics, and medical research. However, little is known regarding the structure of the three-dimensional networks in which the worms become entangled and possibly branched, especially at high concentrations. What is known is that this composition results in two distinctive fluid characteristics: viscoelasticity and strain-birefringence. The latter is exploited in this work in order to study the shear wave speed and attenuation in 500/300mM CTAB/NaSal fluid. Three different experiments were conducted using either a …


Dynamic Feature Extraction And User Classification Using Touchanalytics™, Clay Mcleod Jan 2014

Dynamic Feature Extraction And User Classification Using Touchanalytics™, Clay Mcleod

Honors Theses

Security systems for modern computing devices suffer from a multitude of weaknesses that can render users helpless against an attack on their system. Various attempts at incorporating human characteristics into security systems have achieved varying levels of success in improving security. In this paper, we study the usefulness of TouchAnalytics™ - a second-level security system that attempts to authenticate a user based on touch-data gathered from an interaction with the device. Through the use of machine learning algorithms, we developed a system that is successful at au- thenticating users, achieving under 0.05% False Authentication Rate (FAR). We conclude that the …


Synthesis And Characterization Of A New Bimetallic Catalyst, Gjl-46, And Its Use In The Catalytic Hydrosilylation Of Phenylacetylene, Gabriel J. Labonia Jan 2014

Synthesis And Characterization Of A New Bimetallic Catalyst, Gjl-46, And Its Use In The Catalytic Hydrosilylation Of Phenylacetylene, Gabriel J. Labonia

Honors Theses

A new bimetallic catalyst was synthesized from the metalation of 1,1'-(1,3-phenylene) bis(4-butyl-1 H-1,2,4-triazol-4-ium) iodide with silver oxide and the transmetalation of that complex with Rh(COD)2OTf. The structure of the compound, GJL-46, with molecular formula C34H46I2N6Rh2, was confirmed with mass spectra analysis, 1H NMR and 13C NMR. The catalytic activity of the produced molecule, GJL-46, with molecular formula C34H46I2N6Rh2, in the hydrosilylation of phenylacetylene is reported.


The Tutte Polynomial Formula For The Class Of Twisted Wheel Graphs, Amanda Hall Jan 2014

The Tutte Polynomial Formula For The Class Of Twisted Wheel Graphs, Amanda Hall

Honors Theses

The 20th century work of William T. Tutte developed a graph polynomial that is modernly known as the Tutte polynomial. Graph polynomials, such as the Tutte polynomial, the chromatic polynomial, and the Jones polynomial, are at the heart of combinatorical and algebraic graph theory and can be used as tools with which to study graph invariants. Graph invariants, such as order, degree, size, and connectivity which are defined in Section 2, are graph properties preserved under all isomorphisms of a graph. Thus any graph polynomial is not dependent upon a particular labeling or drawing but presents relevant information about the …


Automated Classification Of Malignant Melanoma Based On Detection Of Atypical Pigment Network In Dermoscopy Images Of Skin Lesions, Nabin K. Mishra Jan 2014

Automated Classification Of Malignant Melanoma Based On Detection Of Atypical Pigment Network In Dermoscopy Images Of Skin Lesions, Nabin K. Mishra

Doctoral Dissertations

“Melanoma causes more deaths than any other form of skin cancer. Early melanoma detection is important to prevent progression to a more deadly stage. Automated computer-based identification of melanoma from dermoscopic images of skin lesions is the most efficient method in early diagnosis. An automated melanoma identification system must include multiple steps, involving lesion segmentation, feature extraction, feature combination and classification. In this research, a classifier-based approach for automatically selecting a lesion border mask for segmentation of dermoscopic skin lesion images is presented. A logistic regression based model selects a single lesion border mask from multiple border masks generated by …


Biomineralization Of Carbonates In Modern Microbial Sediments And Its Implications For Co₂ Sequestration, Varun Gnanaprian Paul Jan 2014

Biomineralization Of Carbonates In Modern Microbial Sediments And Its Implications For Co₂ Sequestration, Varun Gnanaprian Paul

Doctoral Dissertations

"Several bacterial species influence carbonate mineral precipitation by modifying pH, alkalinity, Ca²⁺ activity and by providing nucleation sites for mineralization. Two studies have been undertaken to explore microbial influence in the mineralization of carbonates. In the first study, the ability of sulfate-reducing bacteria (SRB) to induce carbonate mineralization was investigated as a means to enhance mineral sequestration of CO₂. Sulfate-reducing bacteria enriched from hypersaline Storr's Lake, The Bahamas; Lake Estancia, New Mexico; and Great Salt Plains Lake, Oklahoma, were tested in reactors under varying CO₂ concentrations. Carbonate mineral precipitation was achieved only in reactors with Lake Estancia SRB community and …


Graphite Aerogels And The Formation Mechanism Of Unusual Micron-Sized Rod And Helical Structures, Clarissa Ann Wisner Jan 2014

Graphite Aerogels And The Formation Mechanism Of Unusual Micron-Sized Rod And Helical Structures, Clarissa Ann Wisner

Doctoral Dissertations

"Pyrolysis at 800 ºC under argon has shown that polyimide (PI), polyacrylonitrile (PAN), polydicyclopentadiene (DCPD) and polybenzoxazine (PBO) aerogels are all viable alternatives to traditional resorcinol-formaldehyde (RF) aerogels as precursors to amorphous carbon aerogels. Subsequent high temperature pyrolysis at 2300 ºC of such carbon aerogels under helium has shown that amorphous carbon from PI and PBO yields the highest degree of graphitization, whereas from RF aerogels yields the lowest.

Those two types of graphite aerogels include also a high concentration of micron-size columnar and helical (screw-like) structures, whose formation is favored by macroporosity and high nitrogen retention in the 800 …


Seismic Anisotropy And Mantle Flow Beneath Africa And Arabia, Ahmed Abdalla Elsheikh Jan 2014

Seismic Anisotropy And Mantle Flow Beneath Africa And Arabia, Ahmed Abdalla Elsheikh

Doctoral Dissertations

"In spite of numerous studies, the mechanisms for the rifting, uplifting, and volcanism on the African plate remain enigmatic. The most popular hypotheses proposed for explaining these tectonic phenomena involve edge-driven small-scale mantle convection and the thermal or dynamic effects of one or more mantle plumes. In this study we use continental scale shear-wave splitting (SWS) measurements to provide additional constraints on the various models of rifting, uplifting, and volcanism of the Cameroon Volcanic Line (CVL) and the Arabian plate. The splitting of P-to-S converted phases at the core-mantle boundary on the receiver side (XKS including PKS, SKKS, and SKS) …


3d Image Acquisition System For Facial Recognition, James E. Pearson Jan 2014

3d Image Acquisition System For Facial Recognition, James E. Pearson

EWU Masters Thesis Collection

Identification of an individual has been a long standing problem in human existence. It is clear from the rising rates of identity theft and misappropriation of services that current methods employed to identify individuals is ineffectual. The most common way people identify other individuals is via recognition of the subjects face. The speed and accuracy with which one person can identify another person is uncanny leading to the development automated facial recognition systems. The vast majority of these systems use two-dimensional (2D) images imagery to perform facial recognition with limited success. The use of 2D imagery has limitations which cannot …


Divide And Conquer G-Buffer Ray Tracing, Daniel Stokes Jan 2014

Divide And Conquer G-Buffer Ray Tracing, Daniel Stokes

EWU Masters Thesis Collection

No abstract provided.


Iowa Waste Reduction Center Newsletter, January 2014, University Of Northern Iowa. Iowa Waste Reduction Center. Jan 2014

Iowa Waste Reduction Center Newsletter, January 2014, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Inside this Issue:

--- A Note from the Director
--- 2014/2015 Calendars
--- Iowa News
--- National News


Factors That Contribute To The Establishment Of Marine Protected Areas In Western Australia, Andrew Hill Jan 2014

Factors That Contribute To The Establishment Of Marine Protected Areas In Western Australia, Andrew Hill

Theses

Five Marine Protected Area (MPA) establishment processes undertaken between 1998 and 2012 in Western Australia were reviewed using a case study approach to identify factors affecting establishment. While three MPAs were legally created, two were not, despite significant investment in planning, research and public participation. Processes were generally influenced by complex local and strategic planning issues that were significant barriers to legal establishment.

Planning and public participation processes were generally successful at addressing local concerns, deriving consensus and building ownership but ineffectual at addressing key strategic issues. MPA establishment was primarily influenced by the social, economic and political influences rather …


Coupling Graphs, Efficient Algorithms And B-Cell Epitope Prediction, Liang Zhao, Steven C. H. Hoi, Zhenhua Li, Limsoon Wong, Hung Nguyen Jan 2014

Coupling Graphs, Efficient Algorithms And B-Cell Epitope Prediction, Liang Zhao, Steven C. H. Hoi, Zhenhua Li, Limsoon Wong, Hung Nguyen

Research Collection School Of Computing and Information Systems

Coupling graphs are newly introduced in this paper to meet many application needs particularly in the field of bioinformatics. A coupling graph is a two-layer graph complex, in which each node from one layer of the graph complex has at least one connection with the nodes in the other layer, and vice versa. The coupling graph model is sufficiently powerful to capture strong and inherent associations between subgraph pairs in complicated applications. The focus of this paper is on mining algorithms of frequent coupling subgraphs and bioinformatics application. Although existing frequent subgraph mining algorithms are competent to identify frequent subgraphs …


Stability Of Traveling-Wave Solutions For A Schrodinger System With Power-Type Nonlinearities, Nghiem Nguyen, Rushun Tian, Zhi-Qiang Wang Jan 2014

Stability Of Traveling-Wave Solutions For A Schrodinger System With Power-Type Nonlinearities, Nghiem Nguyen, Rushun Tian, Zhi-Qiang Wang

Mathematics and Statistics Faculty Publications

In this article, we consider the Schrodinger system with powertype nonlinearities, (Formula presented) where j = 1,...,m, uj are complex-valued functions of (x, t) 2 RN+1, a, b are real numbers. It is shown that when b > 0, and a + (m - 1)b > 0, for a certain range of p, traveling-wave solutions of this system exist, and are orbitally stable.


A Shortcut For Multiple Testing On The Directed Acyclic Graph Of Gene Ontology, Garrett Saunders, John R. Stevens, S. Clay Isom Jan 2014

A Shortcut For Multiple Testing On The Directed Acyclic Graph Of Gene Ontology, Garrett Saunders, John R. Stevens, S. Clay Isom

Mathematics and Statistics Faculty Publications

Background: Gene set testing has become an important analysis technique in high throughput microarray and next generation sequencing studies for uncovering patterns of differential expression of various biological processes. Often, the large number of gene sets that are tested simultaneously require some sort of multiplicity correction to account for the multiplicity effect. This work provides a substantial computational improvement to an existing familywise error rate controlling multiplicity approach (the Focus Level method) for gene set testing in high throughput microarray and next generation sequencing studies using Gene Ontology graphs, which we call the Short Focus Level.

Results: The Short Focus …


Dynamical Monodromy, C. Chen, Megan K. Ivory, Seth Aubin, John B. Delos Jan 2014

Dynamical Monodromy, C. Chen, Megan K. Ivory, Seth Aubin, John B. Delos

Arts & Sciences Articles

Integrable Hamiltonian systems are said to display nontrivial monodromy if fundamental action-angle loops defined on phase-space tori change their topological structure when the system is carried around a circuit. In an earlier paper it was shown that this topological change can occur as a result of time evolution under certain rather abstract flows in phase space. In the present paper, we show that the same topological change can occur as a result of application of ordinary forces. We also show how this dynamical phenomenon could be observed experimentally in classical or in quantum systems.