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Full-Text Articles in Physical Sciences and Mathematics

Structural And Sedimentological Analysis Of The Bear Canyon Conglomerate, Southeastern California: Implications For The Timing And Style Of Miocene Deformation Within The Eastern California Shear Zone, Garrett Goff Jan 2019

Structural And Sedimentological Analysis Of The Bear Canyon Conglomerate, Southeastern California: Implications For The Timing And Style Of Miocene Deformation Within The Eastern California Shear Zone, Garrett Goff

Open Access Theses & Dissertations

The region between Indian Pass and Picacho State Recreation Area (PSRA) in southeastern California records complex deformation related to the transition from a Paleogene convergent margin to a Neogene transform setting, although the timing and nature of youngest deformation in this region remains incompletely known. A 1.7 km-thick section of Miocene Bear Canyon conglomerate (BCC) was studied to constrain this young period of deformation. These rocks lie unconformably upon 23 Ma volcanic and epiclastic rocks and a Mesozoic metamorphic basement terrane. Near PSRA the BCC contains locally derived clasts and can be further subdivided into three unconformity-bounded sequences, referred to …


Deciduous Shrub Encroachment Effects On Tundra Soil Properties, Daniela Aguirre Jan 2019

Deciduous Shrub Encroachment Effects On Tundra Soil Properties, Daniela Aguirre

Open Access Theses & Dissertations

Deciduous shrub abundance is increasing in tundra ecosystems as an effect of rising temperatures which may change tundra physical properties and, in turn, microbial communities and biogeochemical processes. Two mechanisms through which shrub presence may affect tundra ecosystems were examined in this study; the physical presence of the shrubs and effects of increasing shrub litter inputs. In a sub-arctic alpine tundra ecosystem, dominated by the deciduous shrub Betula glandulosa, both shrub presence (shrub present and removed) and litter quantity (no litter/litter removed, ambient litter, and twice ambient litter) were manipulated; multiple ecosystem properties where measured within the treatment plots over …


Bayesian Analysis Of Variable-Stress Accelerated Life Testing, Richard Okine Jan 2019

Bayesian Analysis Of Variable-Stress Accelerated Life Testing, Richard Okine

Open Access Theses & Dissertations

Several authors have over the years studied the art of modeling data from accelerated life testing and making inferences from such data. In this study, we consider a continuously varying stress accelerated life testing procedure which is the limiting case of the multiple stress-level discussed by Doksum and H´oyland [1]. We derive the likelihood function for the life distribution of the continuously increasing stress accelerated life testing model and consequently the Fisher's Information Matrix. We propose a Bayesian analysis for this distribution using the Gibbs Sampling Procedure. We conduct simulation studies and real data analysis to demonstrate the efficiency of …


Towards Analytical Techniques For Systems Engineering Applications, Griselda Valdepeñas Acosta Jan 2019

Towards Analytical Techniques For Systems Engineering Applications, Griselda Valdepeñas Acosta

Open Access Theses & Dissertations

One of the main objectives of systems engineering is to design, maintain, and analyze systems that help the users. To design an appropriate system for an application domain, we need to know: what are the users' desires and preferences (so that we know in what direction we should aim to change this domain), what is the current state and what is the dynamics of this application domain, and how to use all this information to select the best alternatives for the system design and maintenance. Designing a system includes selecting numerical values for many of the parameters describing the corresponding …


Forecasting Crashes, Credit Card Default, And Imputation Analysis On Missing Values By The Use Of Neural Networks, Jazmin Quezada Jan 2019

Forecasting Crashes, Credit Card Default, And Imputation Analysis On Missing Values By The Use Of Neural Networks, Jazmin Quezada

Open Access Theses & Dissertations

A neural network is a system of hardware and/or software patterned after the operation of neurons in the human brain. Neural networks,- also called Artificial Neural Networks - are a variety of deep learning technology, which also falls under the umbrella of artificial intelligence, or AI. Recent studies shows that Artificial Neural Network has the highest coefficient of determination (i.e. measure to assess how well a model explains and predicts future outcomes.) in comparison to the K-nearest neighbor classifiers, logistic regression, discriminant analysis, naive Bayesian classifier, and classification trees. In this work, the theoretical description of the neural network methodology …


Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa Jan 2019

Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa

Open Access Theses & Dissertations

Nanotechnology has a great potential in ensuring food production, security and safety globally. Over the past decade, research on the use of nanomaterials to supply nutrient elements and protect plants from pest and diseases has significantly increased. Tomato (Solanum lycopersicum) is one of the most consumed vegetables in the world and United State is one of its largest producers globally generating billions of dollars annually in revenue.. Tomato plants are affected worldwide by Fusarium wilt caused by Fusarium oxysporum f. sp. Lycopersici. There is growing concern about excessive use of conventional pesticides in controlling Fusarium and other diseases in tomato …


Nonlinear Optics For Nanoparticle Tracking And Materials Characterization, Angela Christina Aguilar Jan 2019

Nonlinear Optics For Nanoparticle Tracking And Materials Characterization, Angela Christina Aguilar

Open Access Theses & Dissertations

A high-speed 3D imaging method is developed by integrating ultrafast laser pulse shaping, temporal focusing microscopy and defocused imaging. This system does not require mechanical movement of either the stage or laser beam. Axial scanning is achieved by manipulation of group velocity dispersions on the femtosecond laser spectrum via pulse shaping method by applying modulation functions on an acoustic optical modulator which diffracts the laser spectrum. The scanning depth becomes only dependent on electronic signals which can be tuned to kHz speeds. The volumetric high-speed scanning capability was demonstrated on fluorescent microspheres suspended in a volume of 100 x100 x …


Cantor Sets, Cantorvals, And Their Topological Structure, Ángel Adrián Agüero Jan 2019

Cantor Sets, Cantorvals, And Their Topological Structure, Ángel Adrián Agüero

Open Access Theses & Dissertations

With interesting topological properties, the Cantor set is worth studying for itself. In other areas, topological structures arise that are in fact homeomorphic to the Cantor set. In particular, we see sets that are homeomorphic to the Cantor set which result from the subsums of particular series, as well as linear combinations of algebraic sums of Cantor sets. These also result in what has been termed a Cantorval, which we also investigate.


Creating Spaces For Conversations On Conservation: A Case Study Of Joint Forest Management In East Sikkim, India., Paulami Banerjee Jan 2019

Creating Spaces For Conversations On Conservation: A Case Study Of Joint Forest Management In East Sikkim, India., Paulami Banerjee

Open Access Theses & Dissertations

Successful community-based natural resource management should include both resource professionals and local communities. Recognizing this fact, my research seeks to encourage more locally adaptive and collaborative forest governance that facilitates sustainable development by enabling grassroots participation. Specifically, I explore opportunities for developing a more sustainable relationship between India's Joint Forest Management (JFM) program and rural forest-dependent communities in Sikkim-a remote, northeastern state of India bordering Nepal to the west, the Tibet Autonomous region of China to the north and northeast, and Bhutan to the southeast. As an instrument for sustainable forestry management, JFM seeks to develop partnerships between forest user …


Stratigraphic And Structural Characterization And Evolution Of Exposed Megaflaps Flanking Salt Diapirs, Cora Evelyn Gannaway Dalton Jan 2019

Stratigraphic And Structural Characterization And Evolution Of Exposed Megaflaps Flanking Salt Diapirs, Cora Evelyn Gannaway Dalton

Open Access Theses & Dissertations

A Neoproterozoic salt system exposed in the Willouran Ranges of South Australia and a Mesozoic salt system in the south-central Pyrenees of Spain provide natural laboratories to investigate the stratigraphic and structural development of megaflaps flanking salt diapirs. Megaflaps are near-vertical to overturned, deep minibasin stratal panels that extend far up the flanks of steep diapirs or their equivalent welds. Megaflaps can form by halokinetic drape-folding, contraction, or a combination of these processes. The existing models of megaflap development are based primarily on seismic data, well penetrations, cross-section restorations, and numerical and analog modeling. Investigation of the sedimentology, stratigraphy, and …


The Illusion Of An Abundant End- A Phenomenological Approach To Sustainability: The Progress Trap And The Transformative Potential Of Dialogue, Shantanu Rojatkar Jan 2019

The Illusion Of An Abundant End- A Phenomenological Approach To Sustainability: The Progress Trap And The Transformative Potential Of Dialogue, Shantanu Rojatkar

Open Access Theses & Dissertations

Abundance is a concept according to which a thing is deemed to be in plenty. The feeling of satisfaction and assurance, arising from something that is concretely abundant, serves as a material reason for motivation of a desired action. Just like the stock of food lying in our fridge, ensuring more than just the needs of the moment, the abundance cooks the taste of freedom, freedom from worrying about tomorrow. However, over consumption out of greed as a potential outcome of abundance, could result in the increased capacity of a person in order to reach the initial level of satisfaction. …


Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia Jan 2019

Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia

Open Access Theses & Dissertations

This study provides new insights into the geometry and timing of ductile, syn-metamorphic structures in the central Panamint Mountains of eastern California. The study focused on Surprise Canyon, where exposures of Meso- to Neoproterozoic miogeocline rocks, reworked crystalline basement, and syn-metamorphic granitoids record fabric overprints indicative of at least two distinct dynamo-thermal metamorphic events. Prograde metamorphism at greenschist and amphibolite metamorphic facies conditions occurred during Early Jurassic plutonism based on deformation of a dioritic pluton with a U-Pb date reported here of 175.6 ± 3.2 Ma. Mid Jurassic deformation (D1) generated the main continuous cleavage in the rocks (S1) as …


Using Two-Photon Microscopy To Analyze Arabidopsis Thaliana Leaves Under Autophagy Conditions And Second Harmonic Generation In Collagen, Andres Martin Reyes Jan 2019

Using Two-Photon Microscopy To Analyze Arabidopsis Thaliana Leaves Under Autophagy Conditions And Second Harmonic Generation In Collagen, Andres Martin Reyes

Open Access Theses & Dissertations

Two-photon microscopy has emerged as a highly efficient and effective imaging tool for biological samples. This can be utilized in studying recently emerging technologies and conditions such as the autophagy process in arabidopsis thaliana leaves and second harmonic generation in collagen. Both of these areas of study utilize the two-photon microscopy practice effectively in uncovering more information of the biological nature of examined samples.


Electron Binding Energy Of Polar Molecules Using Fermi Löwdin Orbital Self Interaction Corrected Density Functional Scheme, Peter Obinna Ufondu Jan 2019

Electron Binding Energy Of Polar Molecules Using Fermi Löwdin Orbital Self Interaction Corrected Density Functional Scheme, Peter Obinna Ufondu

Open Access Theses & Dissertations

Density functional theory (DFT) has become a standard method for electronic structure calculations in physics. The standard approximate density functional usually do not bind this class of anions, due to self-interaction error (SIE). We apply the recently developed Fermi Löwdin orbitals based self-interaction correction method (FLOSIC) with long-range diffuse Gaussian functions to study dipole bound anions and negatively charged water clusters. These calculations are carried out using Perdew-Wang (1992) local spin density PW91-LDA, Perdew-Burke-Ernzerhof PBE-GGA, and the recently developed Strongly Constrained and Appropriately Normed SCAN-meta-GGA functional which satisfies all the known constraints for exchange-correlation functional. Plot from FLOSIC density difference …


Magnetic Nanoparticles For Hyperthermia For Cancer Treatment, Bianca Paola Meneses Brassea Jan 2019

Magnetic Nanoparticles For Hyperthermia For Cancer Treatment, Bianca Paola Meneses Brassea

Open Access Theses & Dissertations

Fe3O4 and NixCu4-x magnetic nanoparticles were synthesized using supercritical conditions of liquids and wet chemistry, respectively. Characterization methods (VSM, SEM, TEM, and magnetic hyperthermia) yielded results that prove feasibility for magnetic hyperthermia for cancer treatment.


Strategies To Improve The Electrochemical Of Performance Transition Metal Compounds As Anode Materials For Li-Ion Batteries, Noemi Dominguez Jan 2019

Strategies To Improve The Electrochemical Of Performance Transition Metal Compounds As Anode Materials For Li-Ion Batteries, Noemi Dominguez

Open Access Theses & Dissertations

Nowadays, our society depends on fossil fuels as the main energy source. However, depletion, price fluctuations, and other concerns, such as global warming, have led to an exhaustive research for renewable energy resources. Here is where electrochemical energy systems play a critical role since they can provide power when renewable energy is not available. Among these electrochemical energy storage systems Li-ion batteries (LIBs) have shown higher volumetric, gravimetric, and power density capacities over other battery systems.

However, commercial LIBs are still relying on graphite base materials for the anode. However, graphite possesses a low specific capacity. Recently, transition metal compounds …


The Rhetoric Of Low Carbon Energy Technology Scientists And Engineers, Nicolas Cesar Hernandez Jan 2019

The Rhetoric Of Low Carbon Energy Technology Scientists And Engineers, Nicolas Cesar Hernandez

Open Access Theses & Dissertations

Scholars in the burgeoning field of Energy Communication have successfully contributed to communication studies and environmental communication practice. However, energy communication scholars have largely focused on energy of media coverage, corporate communication and decision making in the context crisis. While rich and informative, this tendency has left quotidian aspects of energy communication rather understudied. As such, this Thesis contributes to the understanding of the internal, non-untechnical rhetoric of low carbon energy technology (LCET) scientists and engineers (herein LCET professionals). Textual analysis was used to examine LCET professionals' internal rhetoric at professional trade conferences and through long form, semi-structured interviews. Wind …


Zircon (U-Th)/He Thermochronologic Investigation Of The Long-Term Thermal History Of Proterozoic Rocks In West Texas And Southern New Mexico, Nathan Zachary Reade Jan 2019

Zircon (U-Th)/He Thermochronologic Investigation Of The Long-Term Thermal History Of Proterozoic Rocks In West Texas And Southern New Mexico, Nathan Zachary Reade

Open Access Theses & Dissertations

The tectonic history of west Texas and southern New Mexico is well documented, however existing geologic data only provide limited snapshots of the region’s prolonged and complex tectonic evolution. Zircon (U-Th)/He (ZHe) thermochronology is used to examine the long-term thermal history of Proterozoic rocks exposed in the southern Rio Grande rift. ZHe data were collected from the Carrizo Mountains (10 dates), Cookes Range (16 dates), and Franklin Mountains (30 dates) in order to constrain the long-term (>1 Ga) thermal history of rocks in this region and relate this history to known tectonic or climatic events. Individual ZHe dates range …


Dimensionality Of Magnetism In Trirutile Cota2o6 And Its Derivatives, Raju Baral Jan 2019

Dimensionality Of Magnetism In Trirutile Cota2o6 And Its Derivatives, Raju Baral

Open Access Theses & Dissertations

In this thesis, we addressed the question of low dimensionality of trirutile compound CoTa2O6 and studied how the low dimensionality evolved with doping of Mg on Co-site. In order to study low dimensionality in CoTa2O6 and its derivative compounds Co1-xMgxTa2O6 (x = 0.1, 0.3, 0.5, 0.7, and 1), we used different techniques: X-ray diffraction, magnetic susceptibility, magnetization, specific heat and elastic neutron diffraction. We have addressed the question of low dimensional magnetism of CoTa2O6 by preparing phase-pure samples of the compound. In CoTa2O6 a broad feature is observed in magnetic susceptibility at 10 K and an antiferromagnetic phase transition is …