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Full-Text Articles in Physical Sciences and Mathematics

Improving Earthquake Disaster Models With Post-Event Data: Insights From The 2015 Gorkha, Nepal Earthquake, Bradley Steven Wilson Dec 2019

Improving Earthquake Disaster Models With Post-Event Data: Insights From The 2015 Gorkha, Nepal Earthquake, Bradley Steven Wilson

Graduate Theses and Dissertations

Immense amounts of data are collected following earthquake disasters. Yet, it remains unclear how researchers’ might take full advantage of diverse post-disaster datasets. Using data from the 2015 Gorkha Nepal earthquake, this dissertation explores three ways in which post- disaster survey and assessment datasets can be used to inform models of seismic risk, vulnerability, and recovery processes. The first article presents an empirical analysis of scale issues in disaster vulnerability indices using a novel dataset of 750,000 households. This study finds that using aggregated household data to create social vulnerability indices can produce results that are meaningfully different from equivalent …


Phylogenetic Reconstruction Analysis On Gene Order And Copy Number Variation, Ruofan Xia Oct 2019

Phylogenetic Reconstruction Analysis On Gene Order And Copy Number Variation, Ruofan Xia

Theses and Dissertations

Genome rearrangement is known as one of the main evolutionary mechanisms on the genomic level. Phylogenetic analysis based on rearrangement played a crucial role in biological research in the past decades, especially with the increasing avail- ability of fully sequenced genomes. In general, phylogenetic analysis aims to solve two problems: Small Parsimony Problem (SPP) and Big Parsimony Problem (BPP). Maximum parsimony is a popular approach for SPP and BPP which relies on itera- tively solving a NP-hard problem, the median problem. As a result, current median solvers and phylogenetic inference methods based on the median problem all face se- rious …


Cool And Warm Season Climate Signals In Tree Rings From North America, Max Carl Arne Torbenson May 2019

Cool And Warm Season Climate Signals In Tree Rings From North America, Max Carl Arne Torbenson

Graduate Theses and Dissertations

Earlywood (EW) and latewood (LW) ring-width chronologies have become an increasingly important proxy in paleoclimate reconstructions. These subannual variables can provide estimates of past hydroclimate variability for seasonal windows that total ring-widths cannot resolve. The strength of the relationship between EW and LW series may influence what type of paleoclimate information is embedded within the tree-ring series. High correlations (> 0.70) between EW and LW are recorded for much of the continent but the magnitude of correlation varies greatly across space and species boundaries. Using four LW chronologies from shortleaf pine, the North American conifer species displaying the lowest EW-LW …


An Analysis Of Postmastectomy Breast Reconstruction Due To Breast Cancer In Nevada And The United States From 2008-2013, Jenna Webb May 2019

An Analysis Of Postmastectomy Breast Reconstruction Due To Breast Cancer In Nevada And The United States From 2008-2013, Jenna Webb

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: In the United States, female breast cancer was the leading cause of new cancer cases from 2011-2015. Since the Women’s Health and Cancer Act of 1998 (WHCRA), the federal government mandates employee and private health insurance providers to cover breast reconstruction if they cover mastectomies. Postmastectomy breast reconstruction (PBR) rates increased after the WHCRA, but these rates have remained relatively low throughout recent years. Objective: The objective of this study was to determine factors associated with women having PBR due to breast cancer in Nevada and the United States from 2008 to 2013. Methods: Using two HCUP database, NIS …


Tree-Ring Reconstructions Of Streamflow For The Tennessee Valley, Sallyrose Anderson, Ross Ogle, Glenn Tootle, Abdoul Oubeidillah Apr 2019

Tree-Ring Reconstructions Of Streamflow For The Tennessee Valley, Sallyrose Anderson, Ross Ogle, Glenn Tootle, Abdoul Oubeidillah

Civil Engineering Faculty Publications and Presentations

This study reports the preliminary results from a statistical screening of tree-ring width records from the International Tree-Ring Data Bank (ITRDB), to evaluate the strength of the hydrological signal, in dendrochronological records from the Tennessee Valley. We used United States Geological Survey (USGS) streamflow data from 11 gages, within the Tennessee Valley, and regional tree-ring chronologies, to analyze the dendroclimatic potential of the region, and create seasonal flow reconstructions. Prescreening methods included correlation, date, and temporal stability analysis of predictors to ensure practical and reliable reconstructions. Seasonal correlation analysis revealed that large numbers of regional tree-ring chronologies were significantly correlated …


Recovering A Random Variable From Conditional Expectations Using Reconstruction Algorithms For The Gauss Radon Transform, Jeremy Becnel, Daniel Riser-Espinoza Jan 2019

Recovering A Random Variable From Conditional Expectations Using Reconstruction Algorithms For The Gauss Radon Transform, Jeremy Becnel, Daniel Riser-Espinoza

Faculty Publications

The Radon transform maps a function on n-dimensional Euclidean space onto its integral over a hyperplane. The fields of modern computerized tomography and medical imaging are fundamentally based on the Radon transform and the computer implementation of the inversion, or reconstruction, techniques of the Radon transform. In this work we use the Radon transform with a Gaussian measure to recover random variables from their conditional expectations. We derive reconstruction algorithms for random variables of unbounded support from samples of conditional expectations and discuss the error inherent in each algorithm.


Iterative Sensitivity Matrix-Based Magnetic Resonance Conductivity Tensor Imaging, Evren Deği̇rmenci̇ Jan 2019

Iterative Sensitivity Matrix-Based Magnetic Resonance Conductivity Tensor Imaging, Evren Deği̇rmenci̇

Turkish Journal of Electrical Engineering and Computer Sciences

Magnetic resonance conductivity tensor imaging (MRCTI) reconstructs high-resolution anisotropic conductivity images, which are proved to have critical importance in radio-oncological imaging as well as source localization fields. In the MRCTI technique, linearly independent current injections are applied to the region to be imaged and resulting magnetic flux densities are measured using magnetic resonance imaging techniques. In this study, a novel iterative reconstruction algorithm based on a sensitivity matrix approach is proposed and tested using both simulated and experimental measurements. Obtained results show that the proposed technique can reconstruct anisotropic conductivity images with high and position-independent spatial resolution in addition to …