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U.S. Hegemonic Control In Latin America: The 1973 Coup In Chile, Seth Wilbur Dec 2022

U.S. Hegemonic Control In Latin America: The 1973 Coup In Chile, Seth Wilbur

LSU New Orleans Theses and Dissertations

On September 11, 1973, the Chilean armed forces staged a coup d’état against their democratically elected and first socialist president, Salvador Allende. The coup ended in Allende’s death and seventeen years of military dictatorship under the auspices of General Augusto Pinochet. Although seemingly a domestic affair, the United States executive branch under the leadership of President Richard Nixon played a significant role in facilitating the coup and it is unlikely the coup would have occurred without U.S. support. While contemporary sources still point to American fears over communist incursion in the western hemisphere as the principal reason for U.S. involvement …


Analysis Of Forensic Artifacts In Database Memory Using Support Vector Machine, Mahfuzul I. Nissan Dec 2022

Analysis Of Forensic Artifacts In Database Memory Using Support Vector Machine, Mahfuzul I. Nissan

LSU New Orleans Theses and Dissertations

Memory analysis allows forensic investigators to establish a more complete timeline of system activity using a snapshot of main memory (i.e., RAM). Investigators may rely on such analysis to detect malicious activity and understand the scope of what data was exfiltrated. This is of particular interest in the presence of incomplete or untrusted logs, where a privileged user (or an attacker with such capabilities) can altogether bypass or disable logging. In such instances, a forensic investigator can still rely on the fact that data must ultimately be processed in memory, regardless of the information that is recorded in audit logs. …


Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu Dec 2022

Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide as a working fluid in a closed Brayton cycle is proving to be more efficient than a conventional steam-based Rankine engine. Understanding the heat transfer properties of supercritical fluids is important for the design of a working engine cycle. The thermophysical properties of supercritical fluids tend to vary non-linearly near the pseudo-critical region. Traditionally, empirical correlations are used to calculate the heat transfer coefficient. It has been shown in the literature and within our own studies that these correlations provide inaccurate predictions near the pseudo-critical line, where heat transfer may be deteriorated or enhanced, resulting from strong …


Insights On Factors Influencing Startup Failure In The Hospitality Industry, Shivangi Khurania Dec 2022

Insights On Factors Influencing Startup Failure In The Hospitality Industry, Shivangi Khurania

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hospitality businesses and innovative startups have faced extremely high failure rates. The author provides insights on the factors that impact startup failure in the hospitality industry after performing a deep analysis on innovation frameworks such as the diffusion of innovation theory, the theory of disruptive innovation, and the ten types of innovation framework. Not only that, the author also provides insights based on their own personal experience and knowledge gained through education at the University of Las Vegas, Nevada. The research explored in this paper revealed that startup failure is not based on one factor alone and how leaders in …


The Emergence Of Serviced Apartments/Apart-Hotels And Opportunities Post Covid-19, Ding Jie Ang Dec 2022

The Emergence Of Serviced Apartments/Apart-Hotels And Opportunities Post Covid-19, Ding Jie Ang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Serviced apartments are becoming more mainstream as people become more aware of this asset class. Since the onset of Covid-19, people have opted for serviced apartments instead of a hotel for self-contained, typically with more space with a living area, kitchen and access to laundry facilities throughout the pandemic. Combined with lower operating costs, higher profit margin, and lower cost per key at development revealed the financial resilience of this asset class as most serviced apartments operated at a higher occupancy than hotels. With renewed interest from developers and owners keen to build or convert their existing properties to serviced …


Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez Dec 2022

Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The fatalities, injuries, and property damage that result from traffic crashes impose a significant burden on society. Current research and practice in traffic safety rely on analysis of quantitative data from crash reports to understand crash severity contributors and develop countermeasures. Despite advances from this effort, quantitative crash data suffers from drawbacks, such as the limited ability to capture all the information relevant to the crashes and the potential errors introduced during data collection. Crash narratives can help address these limitations, as they contain detailed descriptions of the context and sequence of events of the crash. However, the unstructured nature …


Application Of Experimentally Calibrated Numerical Models For Prediction Of Composite Masonry Prism Strength, James Bristow Dec 2022

Application Of Experimentally Calibrated Numerical Models For Prediction Of Composite Masonry Prism Strength, James Bristow

UNLV Theses, Dissertations, Professional Papers, and Capstones

The composite masonry prism test is a common laboratory test to determine the compressive strength of a set of masonry prisms (f’mt) to verify that the composite masonry prism assembly, and more importantly, the constituent materials, are providing adequate strength. While constructing masonry structures, the subcontractors, designers, and inspectors rarely provide continuous supervision or inspection of the construction process. Accordingly, verification of grout mix design, mixed proportions, proper installation of blocks, placement of mortar, dimensions of joints, etc. are more traditionally performed on a periodic basis instead. However, through the use and review of the composite masonry prism test results, …


The Parkinson’S Prison And The Hero’S Journey To Escape: Improvisation And Storytelling In Parkinson’S Disease, Robert David Cochrane Dec 2022

The Parkinson’S Prison And The Hero’S Journey To Escape: Improvisation And Storytelling In Parkinson’S Disease, Robert David Cochrane

UNLV Theses, Dissertations, Professional Papers, and Capstones

Parkinson’s disease (PD) is the fastest growing neurological disorder in the world, with leading researchers calling it a pandemic. While there is no cure, pharmaceuticals and surgical interventions increase people with Parkinson’s (PWP) ability to lead longer and more productive lives. However, there is a lack of care available for PWP supporting their social and emotional domains. PWP report high levels of stress, anxiety, and isolation due to the chronic and unpredictably progressive nature of the disease. This leads to a vicious cycle of loss of confidence, decreased activity and socialization, and increased falls.A common phrase in the PD community …


The Stability Of The Speech-To-Song Illusion And Individual Differences, Rodica R. Constantine Dec 2022

The Stability Of The Speech-To-Song Illusion And Individual Differences, Rodica R. Constantine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Music and language are easily distinguishable for the average listener despite sharing many structural acoustic similarities. The Speech-to-Song illusion can give rise to both musical and linguistic percepts by inducing a perceptual switch after listening to multiple repetitions of a natural spoken utterance. As such, it has been used as a tool to control for low-level acoustic characteristics previously shown to drive lateralized brain responses regardless of domain-type, helping to disambiguate the contribution of high- versus low-level processes in both music and speech perception. However, there exists a lack of research on how large a role individual differences such as …


Anxiety, Depression, And Suicidal Ideation Among Transgender Individuals With Gender Receiving Gender-Affirming Hormone Therapy, Rosa E. Diaz Dec 2022

Anxiety, Depression, And Suicidal Ideation Among Transgender Individuals With Gender Receiving Gender-Affirming Hormone Therapy, Rosa E. Diaz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: Gender may align with one’s sex but doesn’t always and sometimes leads to Gender Dysphoria (GD). Gender-affirming hormone therapy (GAHT) is often one of the first medical treatments used for GD yet few studies have examined the effects of GAHT on mental health (depression, anxiety, and suicidal ideation).Methods: Participants were 18 years or older and self-reported as being diagnosed with GD and recruited across the United States using snowball and convenience sampling. The Patient Health Questionnaire-9 (PHQ-9) was used to measure depression scores, General Anxiety Disorder-7 (GAD-7) was used to measure anxiety scores, and Suicidal Behaviors Questionnaire-Revised (SBQ-R) was …


Effects Of Particle Size And Replacement Proportion Of Post-Consumer Glass In Concrete, Negasi Gebremichael Dec 2022

Effects Of Particle Size And Replacement Proportion Of Post-Consumer Glass In Concrete, Negasi Gebremichael

UNLV Theses, Dissertations, Professional Papers, and Capstones

Concrete, next to water, is the most used material (Gagg, 2014), which consumes natural or manufactured aggregates and resource-intensive cement. Concrete is also a more wasteful construction material than timber and steel. Depleting the natural resource due to aggregate extraction and the environmental unfriendliness of cement production have left the construction industry with no choice. Reducing waste, reusing, or recycling can help conserve natural resources. In this regard, the construction industry constantly seeks full or partial replacement of concrete aggregates and cement with recycled material. Glass is a candidate for replacing the three major components: cement, fine aggregate, and coarse …


A Mechanically Intelligent Hosing-Drone, Blake Hament Dec 2022

A Mechanically Intelligent Hosing-Drone, Blake Hament

UNLV Theses, Dissertations, Professional Papers, and Capstones

This manuscript presents a ”mechanically intelligent” approach to designing a Hosing-Drone for heavy-duty pressure washing. Spraying a hose creates strong reaction forces and torques. Previously demonstrated spraying robots are over-engineered to be very massive with huge inertias. These high inertias ”wash out” the reaction from the spraying. In the proposed approach, the contributions from all observable fluid dynamics, fluid structure interactions, and aerodynamics are studied individually and for the coupled system. Experimental data is collected and fit to dynamic models. These models are used to design a smaller, lighter, more agile vehicle than has been previously demonstrated. An impedance controller …


Covid-19 Isolation Compliance Among Students And Employees Of A Large Public University, Nicolette Harmon Dec 2022

Covid-19 Isolation Compliance Among Students And Employees Of A Large Public University, Nicolette Harmon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Isolation has been used to prevent the spread of many infectious diseases including COVID-19. The CDC’s isolation recommendations have changed over the course of the COVID-19 pandemic, currently infected individuals must stay at home for 5 full days. The CDC cites low compliance rates as one of the reasons for the recent reduction to the number of days in isolation. However, the CDC could only cite studies from other countries due to the lack of studies on isolation compliance in the United States. This study aimed to determine what percentage of UNLV students and staff complied with the isolation guidelines …


Hydrogeologic Heterogeneity Identification: Using Inverse Modeling Of Synthetic Borehole Temperatures To Predict Groundwater Flux, Kevin Heintz Dec 2022

Hydrogeologic Heterogeneity Identification: Using Inverse Modeling Of Synthetic Borehole Temperatures To Predict Groundwater Flux, Kevin Heintz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Heat has been effectively used as a groundwater tracer for decades, and high-resolution temperature data can better identify and quantify discrete flow zones. Refinements to the numerical modeling of advective heat transfer in borehole temperature sensing deployments can improve understanding of dynamic hydrogeologic systems. In my thesis, I develop a novel two-dimensional coupled radial groundwater flow and heat transfer numerical model that considers intra-borehole vertical flow. To test the performance of this model, I used finite element analysis to generate synthetic data sets consisting of prescribed variable flow fields and resulting borehole temperatures. I input synthetic temperatures into the two-dimensional …


Characterization Of The Isothermal Titration Calorimetry Single Injection Method Using T4 Polynucleotide Kinase As A Model System For Kinases, Rebecca Chaehee Lim Dec 2022

Characterization Of The Isothermal Titration Calorimetry Single Injection Method Using T4 Polynucleotide Kinase As A Model System For Kinases, Rebecca Chaehee Lim

UNLV Theses, Dissertations, Professional Papers, and Capstones

Kinases are an important class of enzymes involved in the regulation of different cellular processes. The dysfunctional activity, either hyperactivity or inactivity, of kinases has been associated with many types of diseases, making kinases a major therapeutic target. As of 2020, more than 80 kinase inhibitors have been FDA-approved and have revolutionized the treatment for progressive disorders such as cancers and Alzheimer's diseases. However, there is always the possibility of developing severe side effects or resistance to drugs so the search for new therapeutics must continue with efficiency and accuracy.Isothermal titration calorimetry (ITC) is a state-of-the-art technique specialized in detecting …


Dimensionality Of Natural Auditory Scene Perception: A Factor Analysis Study, Margaret A. Mcmullin Dec 2022

Dimensionality Of Natural Auditory Scene Perception: A Factor Analysis Study, Margaret A. Mcmullin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Theories of auditory and visual scene analysis suggest the perception of scenes relies on the identification and segregation of objects within it, resembling a detail-oriented processing style, but it is possible that a global-oriented process also occurs while evaluating auditory scenes. There is evidence for global properties that enable rapid recognition of visual scenes, even without recognizing the individual objects comprising the scene. It is our understanding that a similar line of research has not been explored in the auditory domain; therefore, we evaluated the contributions of high-level global and low-level acoustic information to auditory scene perception. A secondary aim …


Transient Sources And How To Study Them: Selected Topics In Multi-Messenger Astronomy, Jiawei Luo Dec 2022

Transient Sources And How To Study Them: Selected Topics In Multi-Messenger Astronomy, Jiawei Luo

UNLV Theses, Dissertations, Professional Papers, and Capstones

The discovery of cosmic neutrino flux by IceCube, and the multi-messenger observations of gravitational event GW170817 ushered in the era of multi-messenger astronomy. Since the Universe itself is a natural laboratory, multi-messenger astronomy can help us study the most extreme physics processes in great detail. In this dissertation, we touch on some of the currently unanswered questions involving different types of transient sources and different “messengers” of multi-messenger astronomy. We employ a variety of analysis methods, including machine learning, a method that has not yet been widely adopted in astronomy but is rapidly gaining momentum.We start this dissertation with Chapter …


Effects Of Patellofemoral Pain On Central Activation And Function Of The Gluteus Medius Muscle In Physically Active Females, Michelle Samuel Dec 2022

Effects Of Patellofemoral Pain On Central Activation And Function Of The Gluteus Medius Muscle In Physically Active Females, Michelle Samuel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Patellofemoral pain (PFP) is the most common knee injury among runners, military personnel, adolescents and recreationally active persons. PFP commonly presents as diffuse pain across the anterior knee that increases with activities such as running, squatting, and walking up and down stairs. Nearly 75% of patients with PFP either alter or completely stop physical activity as a result of the pain. There are numerous mechanisms that contribute to PFP symptoms; such as muscle weakness, abnormal joint mechanics and abnormal joint stress, which make it difficult to successfully treat. In addition, PFP may lead to patellofemoral joint (PFJ) osteoarthritis, a debilitating …


Comparing Forgetting Rates Between Pattern Separation And Item Recognition, Rhiannon N. Soriano Smith Dec 2022

Comparing Forgetting Rates Between Pattern Separation And Item Recognition, Rhiannon N. Soriano Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent theories of forgetting posit that hippocampally-based memory representations are more prone to be forgotten due to decay, while extra-hippocampal representations are more likely to be forgotten due to interference (Hardt, Nader, & Nadel, 2013; Sadeh & Pertzov, 2020). The current study examined this hypothesis by comparing the rate of forgetting between pattern separation, a hippocampally-based process, and item recognition, a process that is reliant on both hippocampal and extra-hippocampal structures. It was hypothesized that pattern separation would display more forgetting due to decay because it is a hippocampally-based process, while item recognition would display more forgetting due to interference …


Development And Application Of A Safety Index For Transit Stops: A Case Study From Las Vegas, Nevada, Rithesh Shivuni Dec 2022

Development And Application Of A Safety Index For Transit Stops: A Case Study From Las Vegas, Nevada, Rithesh Shivuni

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research developed a methodology to evaluate safety proximate to transit stops through a Safety Index, identified key factors associated with fatal crashes proximate to bus transit stops, and illustrated the applications of these using a case study based on the Las Vegas metropolitan area in Nevada, USA. The methodology is based on motor vehicle crashes that involve pedestrians recorded in the proximity of transit stops, and the severity of the crash outcomes. It focused on crashes which involved pedestrians that occurred within walking distances of individual transit stops. The severity of the crash outcomes was classified based on the …


Examination Of The Relationship Between Loneliness And Binge Eating Symptoms, Kimberly Stevens Dec 2022

Examination Of The Relationship Between Loneliness And Binge Eating Symptoms, Kimberly Stevens

UNLV Theses, Dissertations, Professional Papers, and Capstones

Loneliness is implicated in several mental health conditions and may also be linked to eating pathology, like binge eating symptoms (e.g., loss-of-control eating). However, the pathways by which loneliness might be associated with binge eating symptoms are less well understood. Preliminary evidence suggests perceived stress may be a key explanatory pathway. Specifically, perceived stress mediates the impact of loneliness on other mental health outcomes and is associated with increased risk of binge eating symptoms. This study investigated relationships between loneliness, perceived stress, and binge eating symptoms and tested whether heightened levels of binge eating was accounted for by increases in …


Real–Time Semantic Segmentation For Railway Anomalies Analysis, Paul Stanik Iii Dec 2022

Real–Time Semantic Segmentation For Railway Anomalies Analysis, Paul Stanik Iii

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the past few years, computer vision has made huge jumps due to deep learning which leverages increased computational power and access to data. The computer vision community has also embraced transparency to accelerate research progress by sharing open datasets and open source code. Access to large scale datasets and benchmark challenges propelled and opened the field. The autonomous vehicle community is a prime example. While there has been significant growth in the automotive vision community, not much has been done in the rail domain. Traditional rail inspection methods require special trains that are run during down time, have sensitive …


Retrospective Varying Coefficient Association Analysis Of Longitudinal Binary Traits, Gang Xu Dec 2022

Retrospective Varying Coefficient Association Analysis Of Longitudinal Binary Traits, Gang Xu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Many genetic studies contain rich information on longitudinal phenotypes that require powerful analytical tools for optimal analysis. Genetic analysis of longitudinal data that incorporates temporal variation is important for understanding the genetic architecture and biological variation of complex diseases. Most of the existing methods assume that the contribution of genetic variants is constant over time and fails to capture the dynamic pattern of disease progression. However, the relative influence of genetic variants on complex traits fluctuates over time.We developed several tests to fill the gap of analyzing time-varying genetic effects in longitudinal GWAS for binary traits. First, we propose a …


Paleoenvironmental Changes Across The Devonian-Carboniferous Transition, Audrey M. Warren Dec 2022

Paleoenvironmental Changes Across The Devonian-Carboniferous Transition, Audrey M. Warren

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Devonian-Carboniferous (D-C) transition was a critical interval in earth history, witnessing profound environmental changes associated with plant and animal evolution and extinction. Two first-order mass extinctions occurred leading up to the D-C boundary: the Kellwasser Event at the Frasnian-Famennian (F-F) boundary (~371 Ma) and the D-C boundary Hangenberg Event (~359 Ma). Both events were associated with significant sea level changes and major carbon cycle perturbations, evidenced by widespread deposition of black shale and positive carbon isotope (δ13C) excursions, all of which have been used to correlate these events across the globe. Because preservation of black shale requires anoxic conditions, …


A Control Integrated Circuit For A Hysteretic Flyback Power Converter, Armani Alvarez Dec 2022

A Control Integrated Circuit For A Hysteretic Flyback Power Converter, Armani Alvarez

UNLV Theses, Dissertations, Professional Papers, and Capstones

This Thesis reports the design, simulation, and layout of a switching power supply controller chip for a fly-back switching power supply. The controller chip was designed using ON’s Semiconductor C5 process. The resulting switching power supply using the controller chip consists of using various off-chip components such as a power MOSFET, transformer, and capacitors. The main components used in the integrated circuit include a bandgap reference voltage circuit which outputs a reference voltage of 1.25V, a ring oscillator having a nominal frequency of 5MHz, a high-gain comparator, and a buffer that can drive a 5pF capacitor. Under normal simulation conditions …


Activity-Based Intervention And One-To-One Correspondence For Children With Developmental Delays, Cyndy Anang Dec 2022

Activity-Based Intervention And One-To-One Correspondence For Children With Developmental Delays, Cyndy Anang

UNLV Theses, Dissertations, Professional Papers, and Capstones

PreK children with developmental delays in inclusive classrooms need access to math interventions helps them develop foundational math skills that are needed to succeed during their K-12 education. Research is significantly lacking that addresses increasing math skills for children with disabilities in PreK classrooms. The purpose of this study was to examine how using activity-based intervention (ABI) increases one-to-one correspondence for children with disabilities in an inclusive classroom. A single subject multiple probe design across participants was implemented to embed one-to-one correspondence math goals into daily routines and preferred activities. The participants of the study were two 3–5-year-old children categorized …


Exploring The Role Of Epistemic Cognition And Self-Efficacy In The Career Decision-Making Processes Of College Students: An Explanatory Sequential Study, Raelynn Frazier Dec 2022

Exploring The Role Of Epistemic Cognition And Self-Efficacy In The Career Decision-Making Processes Of College Students: An Explanatory Sequential Study, Raelynn Frazier

UNLV Theses, Dissertations, Professional Papers, and Capstones

College students are asked to make critical decisions about which academic major to choose and subsequently to make specific career decisions. Students come to college with a myriad of different skill sets, backgrounds, developmental levels, cognitive processes, familial support, and levels of self-efficacy that may influence how they make these decisions. The purpose of this study was to explore the role that epistemic cognition and self-efficacy may play in the career decision-making processes of college students utilizing a mixed methods approach. Results of this study indicate that there are internal and external influences that impact college students’ career decision-making processes …


Improved Computational Prediction Of Function And Structural Representation Of Self-Cleaving Ribozymes With Enhanced Parameter Selection And Library Design, James D. Beck Dec 2022

Improved Computational Prediction Of Function And Structural Representation Of Self-Cleaving Ribozymes With Enhanced Parameter Selection And Library Design, James D. Beck

Boise State University Theses and Dissertations

Biomolecules could be engineered to solve many societal challenges, including disease diagnosis and treatment, environmental sustainability, and food security. However, our limited understanding of how mutational variants alter molecular structures and functional performance has constrained the potential of important technological advances, such as high-throughput sequencing and gene editing. Ribonuleic Acid (RNA) sequences are thought to play a central role within many of these challenges. Their continual discovery throughout all domains of life is evidence of their significant biological importance (Weinreb et al., 2016). The self-cleaving ribozyme is a class of noncoding Ribonuleic Acid (ncRNA) that has been useful for …


Heteroepitaxy Of Gasb On Gaas (111)A For Electron Transport Studies, Madison Drake Dec 2022

Heteroepitaxy Of Gasb On Gaas (111)A For Electron Transport Studies, Madison Drake

Boise State University Theses and Dissertations

III-V semiconductors grown by molecular beam epitaxy (MBE) on (111) surfaces have some interesting electronic properties. For certain materials with a (111)-orientation, the Γ- and L-valleys are reasonably close in energy. This means that it may be possible to take advantage of electron conduction in the L- and Γ-valleys at the same time, allowing us to overcome the so-called “density-of-states bottleneck,” and enable transistors with large drive currents.1 We have investigated this phenomenon in GaSb- and InAs-based 2D electron gases for which the electron effective masses are low.

However, growth of materials with a (111) orientation is typically more …


The Exoskeleton Of Environmental Law: Why The Breadth, Depth, And Longevity Of Environmental Law Matters For Judicial Review, Sanne H. Knudsen Dec 2022

The Exoskeleton Of Environmental Law: Why The Breadth, Depth, And Longevity Of Environmental Law Matters For Judicial Review, Sanne H. Knudsen

Utah Law Review

Environmental law is pragmatic, inevitable, and intentional. In the aggregate, the numerous federal environmental statutes are not simply a patchwork of ad hoc responses or momentary political breakthroughs to isolated public health problems and resource concerns. Together, they are a group of repeated, legislatively-backed commitments to embrace selfrestraint for self-preservation.

Self-restraint and discipline are the essence of environmental law. Indeed, if one studies the patterns and repeated choices in environmental law’s many statutory texts, one can start to appreciate environmental law’s indispensable role in society: it serves as an enduring “exoskeleton,” a sort of protective armor created over time to …