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Full-Text Articles in Physical Sciences and Mathematics

Summer Land Surface Temperature: Small-Local Variation In Intro-Urban Environment In El Paso, Tx, Mactar Mohamed Jan 2013

Summer Land Surface Temperature: Small-Local Variation In Intro-Urban Environment In El Paso, Tx, Mactar Mohamed

Open Access Theses & Dissertations

ABSTRACT

It has been well documented that rapid urbanization and population growth have led to the transformation of the natural landscape into anthropogenic urban land and changed such surface physical properties as albedo, energy balance, and surface roughness. Cities, therefore, will be warmer at the urban areas than the rural lands; this situation creates a phenomenon called Urban Heat Island (UHI).

In the recent decades, numerous approaches to study the variation of land surface temperature during daytime have emerged; however, little is known about the variation during nighttime. This study addressed the spatial variation of Summer Nighttime Land Surface Temperature …


Rbd2po4: Room Temprature Synthesis, Chemical And Structural Stablity Upon Heating, Masoud Mollaee Jan 2013

Rbd2po4: Room Temprature Synthesis, Chemical And Structural Stablity Upon Heating, Masoud Mollaee

Open Access Theses & Dissertations

Monoclinic RbD2PO4 polycrystals were synthesized via the room temperature crystallization of RbH2PO4 dissolved in D2O. Powder x-ray diffraction (XRD) data collected at T=25 ºC indicate that this deuterated compound crystallizes in space group P21/m with unit cell parameters a=7.688í?, b=6.192í?, c=4.781í? and β=109.02°, and is isomorphic with the intermediate-temperature phase of its hydrogenated counterpart rubidium dihydrogen phosphate (RDP). We found no evidence of previously reported [Phase Transitions 80, 17 (2007)] polymorphic phase transition in rubidium dideuterium phosphate (DRDP) upon heating from room temperature to 210 ºC. All lattice parameters vary smoothly within this temperature range, demonstrating that the P21/m phase …


Impact Of Cerium Oxide Nanoparticles On Cilantro (Coriandrum Sativum), Maria Isabel Morales Jan 2013

Impact Of Cerium Oxide Nanoparticles On Cilantro (Coriandrum Sativum), Maria Isabel Morales

Open Access Theses & Dissertations

Studies have shown that plants exposed to ENPs suffer different types of stress. Other studies have revealed that plants can take up and accumulate CeO2 NPs without modification. Thus, these NPs could enter the food chain through edible plants, posing a threat for human health. Cilantro (Coriandrum sativum) is a worldwide culinary and medicinal plant consumed either as a fresh herb or a spice. In this research, cilantro plants were germinated and cultivated for 30 days in organic soil treated with CeO2 NPs at concentrations varying from 0 to 500 mg kg!1. Subsequently, plant organs were analyzed by using spectroscopic …


Model Fusion: A New Approach To Processing Heterogeneous Data, Omar Ochoa Jan 2013

Model Fusion: A New Approach To Processing Heterogeneous Data, Omar Ochoa

Open Access Theses & Dissertations

In many practical situations, it is necessary to extract

information from data of different types. For example, in geosciences, several sources of data can be used to determine the interior structure of the earth: the first arriving waves from earthquakes and from man-made sources, measurements of the earth's gravity field, measurements of the dispersion of surface waves generated by earthquakes, etc. At present, most existing data processing techniques deal only with data of one type.

A joint use of all the information derived from multiple types of data sources is an important theoretical and practical challenge. Such a joint use …


Strong Coupled Quark Matter And Drawbacks Of Its Bcs-Bec Crossover, Israel Portillo Vazquez Jan 2013

Strong Coupled Quark Matter And Drawbacks Of Its Bcs-Bec Crossover, Israel Portillo Vazquez

Open Access Theses & Dissertations

It was found many years ago, that the ground state wave functions of the Bardeen-Cooper-Schrieer (BCS) superconductivity in a degenerate Fermi gas and the Bose-Einstein condensation (BEC) of composite molecules are essentially the same, and those two states can be smoothly connected through a crossover. This BCS-BEC crossover has being recently extended to relativistic Fermi System. This thesis is dedicated to exploring the possible crossover from BEC to BCS phase on strong-interacting matter and its implications for the system Equation of State. The study will be concentrated on dierent phases of dense quark-matter for vanishing temperatures and densities beyond hadronic …


Photochemical Synthesis Of Amino Acid And Peptide Oxo-Esters, Alfredo Ornelas Jan 2013

Photochemical Synthesis Of Amino Acid And Peptide Oxo-Esters, Alfredo Ornelas

Open Access Theses & Dissertations

Amino acid and peptide oxo-esters have played an important role in peptide chemistry for many years. Various amino acid esters are commonly used as protecting groups for peptide synthesis in solution. Moreover, activated phenyl ester derivatives have been used for chemical ligation of peptides. However, the synthesis of amino acid and peptide oxo-esters is commonly performed under acidic or basic conditions. Under acidic conditions, acid-sensitive protecting groups may be cleaved, and under basic conditions racemization of amino acid esters is a common problem. Here we present the photochemical synthesis of amino acid and peptide oxo-esters. Based on the photochemical properties …


Novel Copper (Ii) Mediated Transfection Nano-Systems And Biological Properties Of Pyridinium Surfactants, Sarit Pal Jan 2013

Novel Copper (Ii) Mediated Transfection Nano-Systems And Biological Properties Of Pyridinium Surfactants, Sarit Pal

Open Access Theses & Dissertations

Efficacy of gene therapy is relied upon the improvement of gene delivery vectors into mammalian cells. Although viral-based polynucleotide carriers are still considered as the most common method for gene delivery but the cost effectiveness, nonspecific lethal immune response has evoked the renaissance of non-viral synthetic delivery systems. An initial discovery by Felgnar et al showed Cationic Liposomes (CLs) (having an overall positive charge) when mixed with DNA to form CL-DNA complexes can enhance the transfer of polynucleotides into cells followed by its expression. Presently, a flurry of experimental works is taking place for the better understanding of structural characterization …


Two-Photon Microscopy Of Nanoparticles And Biotissues, Judith Noemi Rivera Jan 2013

Two-Photon Microscopy Of Nanoparticles And Biotissues, Judith Noemi Rivera

Open Access Theses & Dissertations

Biomedical Imaging is an important tool in medical research and clinical practice. From understanding the fundamental processes involved in our biological makeup to its use in diagnostics in helping determine what ails us, the advancements in imaging and microscopy have helped shape our view of the world and nature. Microscopy in particular is often used to study the smallest of cells and their dynamical properties while attempting to minimally change the sample being studied. My research objective is largely divided into two parts. The first part consists of designing a video-rate raster scanning two-photon microscope that is faster than current …


Unconstrained L1 Optimization With Applications To Signal And Image Processing, Carlos Andres Ramirez Jan 2013

Unconstrained L1 Optimization With Applications To Signal And Image Processing, Carlos Andres Ramirez

Open Access Theses & Dissertations

In recent years, the applied mathematical community has witnessed a revolution that is changing the paradigm of classical signal and image processing. Novel and e efficient numerical algorithms have emerged for solving new challenges in large scale signal retrieval, where both constrained and unconstrained L1 minimization methods play a fundamental role.

In this work, we present a new methodology for solving unconstrained L1 minimization problems in the context of image and signal processing. Our approach consists in solving a sequence of relaxed unconstrained minimization problems depending on a positive regularization parameter that converges to zero. The optimality conditions of each …


A Convex Optimization Algorithm For Sparse Representation And Applications In Classification Problems, Reinaldo Sanchez Arias Jan 2013

A Convex Optimization Algorithm For Sparse Representation And Applications In Classification Problems, Reinaldo Sanchez Arias

Open Access Theses & Dissertations

In pattern recognition and machine learning, a classification problem refers to finding an algorithm for assigning a given input data into one of several categories. Many natural signals are sparse or compressible in the sense that they have short representations when expressed in a suitable basis. Motivated by the recent successful development of algorithms for sparse signal recovery, we apply the selective nature of sparse representation to perform classification. Any test sample is represented in an overcomplete dictionary with the training sample as base elements. A given test sample can be expressed as a linear combination of only those training …


On Different Techniques For The Calculation Of Bouguer Gravity Anomalies For Joint Inversion And Model Fusion Of Geophysical Data In The Rio Grande Rift, Azucena Zamora Jan 2013

On Different Techniques For The Calculation Of Bouguer Gravity Anomalies For Joint Inversion And Model Fusion Of Geophysical Data In The Rio Grande Rift, Azucena Zamora

Open Access Theses & Dissertations

Density variations in the Earth result from different material properties, which reflect the tectonic processes attributed to a region. Density variations can be identified through measurable material properties, such as seismic velocities, gravity field, magnetic field, etc. Gravity anomaly inversions are particularly sensitive to density variations but suffer from significant non-uniqueness. However, using inverse models with gravity Bouguer anomalies and other geophysical data, we can determine three dimensional structural and geological properties of the given area. We explore different techniques for the calculation of Bouguer gravity anomalies for their use in joint inversion of multiple geophysical data sets and a …


Utilizing Cyber Espionage To Combat Terrorism, Gary Adkins Jan 2013

Utilizing Cyber Espionage To Combat Terrorism, Gary Adkins

Open Access Theses & Dissertations

The world has effectively exited the Industrial Age and is firmly planted in the Information Age. Global communication at the speed of light has been a great asset to both businesses and private citizens. However, there is a dark side to the age we live in, where terrorist groups are able to communicate, plan, fund, recruit, and spread their message to the world. The relative anonymity the internet provides hinders law enforcement and security agencies in not only locating would-be terrorists but also in disrupting their operations. The internet is a loosely knit group of computers and routers and is …


Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides Jan 2013

Olivine Ca Content Measured By Icp-Oes To Estimate P-T, Bradley Benavides

Open Access Theses & Dissertations

Ca is a trace element in olivine and its concentration is pressure and temperature dependent, providing a rare opportunity to estimate pressure conditions at which mantle-derived rocks (xenoliths) last equilibrated. This P-T dependence has previously been calibrated for mantle xenoliths, and we applied this technique to samples from Jasper Seamount (Jasper Seamount), an oceanic intraplate volcano (OIV) off the coast of the Baja California Peninsula of Mexico. Preliminary compositions for xenoliths from this location appear to define a magmatic plumbing system that features magma storage near the bottom of the crust. A more detailed analysis of the samples is required …


Post-Pareto Optimality Methods For The Analysis Of Large Pareto Sets In Multi-Objective Optimization, Victor Manuel Carrillo Jan 2013

Post-Pareto Optimality Methods For The Analysis Of Large Pareto Sets In Multi-Objective Optimization, Victor Manuel Carrillo

Open Access Theses & Dissertations

Multiple objective optimization involves the simultaneous optimization of more than one, possibly conflicting, objectives. Multiple objective optimization problems arise in a variety of real-world applications. In general, the main difference between single and multi-objective optimization is that in multi-objective optimization there is usually no single optimal solution, but a set of equally good alternatives with different trade-offs, also known as Pareto-optimal solutions. There are two general approaches to solve multiple objective optimization problems: mathematical methods and meta-heuristic methods. The first approach involves the aggregation of the attributes into a linear combination of the objective functions, also known as scalarization. The …


A Semantic Web-Based Methodology For Describing Scientific Research Efforts, Aida Gandara Jan 2013

A Semantic Web-Based Methodology For Describing Scientific Research Efforts, Aida Gandara

Open Access Theses & Dissertations

Scientists produce research resources that are useful to future research and innovative efforts. In a typical scientific scenario, the results created by a collaborative team often include numerous artifacts, observations and relationships relevant to research findings, such as programs that generate data, parameters that impact outputs, workflows that describe processes, and publications, posters and presentations that explain results and findings. Scientists have options in what results to share and how to share them, however, there is no systematic approach to documenting scientific research and sharing it on the Web.

The goal of this research is to define a systematic approach …


Assessing The Equity Implications Of Greenspace Distribution In An Arid Region, Abdelatif Eldeb Jan 2013

Assessing The Equity Implications Of Greenspace Distribution In An Arid Region, Abdelatif Eldeb

Open Access Theses & Dissertations

In the last few decades, vegetation deterioration is receiving increased attention because of its adverse impacts on societal and human health, environmental sustainability, and quality of life. I have selected two cities in Chihuahua Desert region (El Paso and Juarez) as case study sites to develop a novel and applicable methodology for integrating remotely sensed data of different spectral and spatial resolutions into an analysis of the spatial distribution of an urban amenity. The primary objective of this research is to determine if the spatial distribution of greenspace in 2010 is equitable with respect to socio-demographics in El Paso and …


Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano Jan 2013

Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano

Open Access Theses & Dissertations

Glucocorticoids are a class of steroid hormones that can either be produced synthetically or naturally by the adrenal glands. The synthetic glucocorticoids are highly prescribed in the United States for their anti-inflammatory and immunosuppressive properties to treat a variety of ailments and diseases; however, these have been implicated in a number of adverse human conditions such as obesity, metabolic syndrome, immune-suppression, delayed puberty, adrenal insufficiency and Cushing Syndrome, among others. Ongoing research has shown that synthetic and natural hormones are transported to aquatic environments via mammalian excretion or wastewater effluent, and as a result, the release of glucocorticoids into the …


The Eolian-Sabkha Transition In The Permian Cedar Mesa Sandstone, Se Utah, Alexandra Massad Jan 2013

The Eolian-Sabkha Transition In The Permian Cedar Mesa Sandstone, Se Utah, Alexandra Massad

Open Access Theses & Dissertations

This study focuses on the depositional transition between the Permian Cedar Mesa sand dune sea and the adjoining fluvial, lacustrine, playa and a sabkha facies. This transition provides insights into how climate and environment interacted in this unique setting where up to 300 m of eolian sands transition into evaporites. The evaporites are less common as tongues within the eolianites than previously thought and there were several environments that were observed that haven't been previously described or observed in the Cedar Mesa. The arrangement of the various units within the study area support the climate control on stratigraphy.

The intertonguing …


Organic Photovoltaics: A Charge Transfer Perspective In The Study Of Donor-Acceptor Systems, Marco Olguin Jan 2013

Organic Photovoltaics: A Charge Transfer Perspective In The Study Of Donor-Acceptor Systems, Marco Olguin

Open Access Theses & Dissertations

The present research involves the study of donor-acceptor (D/A) dyad complexes from a charge transfer energy perspective. The aim is to provide insight and predictive understanding into the charge transfer processes of the molecular-level components in donor-acceptor based organic solar cells using computational methods to describe photochemical processes at the quantum mechanical level within the Density Functional Theory (DFT) approximation. Predictive understanding is anchored in reproducing experimental results, wherein the present work a perturbative excited-state DFT method is described in detail and shown to give Charge Transfer (CT) energies in excellent agreement with benchmark experimental data. With an accurate excited …


Surface Plasmon Polaritons And Waveguide Modes At Structured And Inhomogeneous Surfaces, Javier Polanco Jan 2013

Surface Plasmon Polaritons And Waveguide Modes At Structured And Inhomogeneous Surfaces, Javier Polanco

Open Access Theses & Dissertations

In chapter 1, properties of a p-polarized surface plasmon polariton are studied, propagating circumferentially around a portion of a cylindrical interface between vacuum and a metal, a situation investigated earlier by M. V. Berry (J. Phys. A: Math. Gen. 8, (1975) 1952). When the metal is convex toward the vacuum this mode is radiative and consequently is attenuated as it propagates on the cylindrical surface. An approximate analytic solution of the dispersion relation for this wave is obtained by an approach different from the one used by Berry, and plots of the real and imaginary parts of its wave number …


Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg Jan 2013

Depositional Setting And Sequence Stratigraphic Analysis Of The Lower Permian Lower Hueco Formation On The Western Margin Of The Orogrande Basin, South Central New Mexico, Jonathon Eric Stautberg

Open Access Theses & Dissertations

On the western margin of the Orogrande Basin in south-central New Mexico, eight outcrop datasets, in the form of measured stratigraphic sections from the lower interval of the Lower Permian Lower Hueco Formation were analyzed in regard to depositional facies distribution and sequence stratigraphy. Based on petrographic analysis of 247 samples and associated field relationships, 11 depositional facies are recognized: 1) quartz sandstone, 2) quartz siltstone and shale, 3) fenestral dolomudstone, 4) microbial intraclast packstone, 5) dolomudstone, 6) green-algal packstone to grainstone, 7) ostracode foram wackestone, 8) oolitic packstone, 9) fossiliferous packstone and grainstone, 10) fusulinid packstone and grainstone, 11) …


Cjc: An Extensible Checker For The Cleanjava Annotation Language, Cesar Eduardo Yeep Jan 2013

Cjc: An Extensible Checker For The Cleanjava Annotation Language, Cesar Eduardo Yeep

Open Access Theses & Dissertations

Formal program verification can be used as a complementary technique to software testing. It allows checking the correctness of all the states of a program which may be impossible using only software testing as a verification technique. One software development process that relies on formal verification is Cleanroom Software Engineering. Cleanroom's main principles are to certify the software with respect to its specification and to produce zero-fault or near-zero-fault software. Cleanroom has being tested primarily in safety-critical systems that require a high level of correctness by development teams in places such as NASA and IBM, demonstrating lower fault rates and …


Comparison Of Bayesian Nonparametric Density Estimation Methods, Adel Bedoui Jan 2013

Comparison Of Bayesian Nonparametric Density Estimation Methods, Adel Bedoui

Open Access Theses & Dissertations

Density estimation has a long history in statistics. There are two main approaches to density, estimation parametric and nonparametric. The first approach requires specification of a family of densities f and estimation of the unknown parameter $\theta$ using a suitable estimation method, for example, maximum likelihood estimation. This approach may be prone to bias that arises from either estimation of the parameter or from incorrect specification of the probability distribution. The second approach, does not assume a specific parametric family.

In this thesis, we implement three density estimation methods that use Bayesian nonparametric approaches utilizing Markov Chain Monte Carlo methods. …


Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley Jan 2013

Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley

Open Access Theses & Dissertations

The last 30 years materials engineers have been under continual pressure to develop materials with a greater temperature potential or to produce configurations that can be effectively cooled or otherwise protected at elevated temperature conditions. Turbines and thrust chambers produce some of the harshest service conditions for materials which lead to the challenges engineers face in order to increase the efficiencies of current technologies due to the energy crisis that the world is facing. The key tasks for the future of gas turbines are to increase overall efficiencies to meet energy demands of a growing world population and reduce the …


Improved Efficiency Of Rna Secondary Structure Prediction Using Distributed Computing, Gerardo A. Cardenas Jan 2013

Improved Efficiency Of Rna Secondary Structure Prediction Using Distributed Computing, Gerardo A. Cardenas

Open Access Theses & Dissertations

The rapidly growing amounts of available biomolecular sequence data, which may represent information from small gene fragments to large complete genomes, have led to the a great need for powerful computational resources for data analysis and storage. With the decoding of the human and other genomes, RNA secondary structure prediction has become an important area of interest in biology and medicine because they help in understanding the mechanisms of many biological processes such as gene regulation and viral replication, and in designing RNA-based therapies to treat various diseases. Due to the complexity of their algorithms, many existing and upcoming computational …


Functional Data Analysis To Guide A Conditional Likelihood Regression In A Case-Crossover Study Investigating Whether Social Characteristics Modify The Health Effects Of Air Pollution, Juana Maribel Herrera Hernandez Jan 2013

Functional Data Analysis To Guide A Conditional Likelihood Regression In A Case-Crossover Study Investigating Whether Social Characteristics Modify The Health Effects Of Air Pollution, Juana Maribel Herrera Hernandez

Open Access Theses & Dissertations

In this study we are focused on exploring whether social characteristics modify the relationship between air pollution and hospitalizations due to asthma or chronic pulmonary obstructive disease (COPD) in El Paso, Tx. The case-crossover design with conditional regression analysis was used, here the controls and the case are the same subject at different

times and has the advantage of removing confounding by permanently confounding factors. Social characteristics are included in the models as interactions with the pollutants, variables included are age, sex, ethnicity and insurance status as indicator for the socio-economic status. The pollutant's lags were chosen using the historical …


Security Games With Interval Uncertainty, Md Towhidul Islam Jan 2013

Security Games With Interval Uncertainty, Md Towhidul Islam

Open Access Theses & Dissertations

Game theory has become an important tool in solving real-life decision making problems. Security games use the concept of game theory in adversarial scenarios to protect critical infrastructure. The main purpose of security games is to allocate security resources among various targets and maximize payoff for the defender considering various kinds of attackers. It is hard for domain experts to predict the attacker's behavior, so one of the major challenges in describing this game model is representing uncertainty about the attacker's payoff. Several approaches have been developed to generate these game models based on uncertainty, such as Bayesian games. However …


Upgrades To Nrlmol Code, Luis Basurto Jan 2013

Upgrades To Nrlmol Code, Luis Basurto

Open Access Theses & Dissertations

This project consists of performing upgrades to the massively parallel NRLMOL electronic structure code in order to enhance its performance by increasing its flexibility by: a) Utilizing dynamically allocated arrays, b) Executing in a parallel environment sections of the program that were previously executed in a serial mode, c) Exploring simultaneous concurrent executions of the program through the use of an already existing MPI environment; thus enabling the simulation of larger systems than it is currently capable of performing. Also developed was a graphical user interface that will allow less experienced users to start performing electronic structure calculations by aiding …


Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller Jan 2013

Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller

Open Access Theses & Dissertations

Arctic environments have gained interest recently due to their sensitivity to climate change. As warming has created longer growing seasons, extended ice-free periods as well as permafrost thaw, the production in freshwater ecosystems has the potential to be greatly impacted. It is hypothesized that as climate change and warming occurs, increases in primary production will occur and ponds will become carbon sinks. Net ecosystem production (NEP) was determined using phytoplankton and periphyton samples collected weekly during the growing season (June - August) from arctic tundra ponds near Barrow, Alaska. Enrichment with 14C was used to determine both weekly photosynthetic rates …


Analysis Of Vehicle Interactions On Interstate Highways: Discrete Choice And Linear System Approaches, Alicia Romo Jan 2013

Analysis Of Vehicle Interactions On Interstate Highways: Discrete Choice And Linear System Approaches, Alicia Romo

Open Access Theses & Dissertations

The research in this dissertation developed statistical and linear system models to predict driving behavior according to driver attributes, vehicle characteristics, car-following dynamics and/or driving conditions. The scope of this research was limited to the interaction of two vehicles traveling in the same direction on interstate highways.

The statistical models proposed in this research investigated the contributions of the different vehicle types on the manner and likelihood of collision. Discrete choice models were used to estimate the probability of the types of collision (rear-end, angle and sideswipe) as functions of driver attributes, striking and struck vehicle types, pre-crash driving actions …