Digital Commons Network^™

Numerical Study Of Oxidation In Stainless Steel Alloy Ep-823 By Liquid Lead-Bismuth Eutectic, Rajyalakshmi Palaparty

UNLV Theses, Dissertations, Professional Papers, and Capstones

The oxidation of stainless steel is influenced by the presence of oxygen in the surrounding medium; the oxygen reacts with the alloy to form an oxide. In certain environments, such as nuclear reactor coolant systems, minimal oxidation of the stainless steel containment functions as a protective shield from corrosive coolants such as liquid lead-bismuth eutectic.

In the current study, this minimal oxidation is evaluated for a system in which corrosion-resistant stainless steel alloy EP-823 is subject to an environment of flowing oxygenated liquid lead-bismuth eutectic at a temperature of 743 K, whereby the thickness of the forming oxide layer is …

Evaluation Of A Continuous Air Monitoring System On An Unmanned Aerial Vehicle For Measurement Of Airborne Radioactive Material, Adam Pfannenstein

UNLV Theses, Dissertations, Professional Papers, and Capstones

The release of airborne radioactive material presents a health risk hazard to many individuals, emergency responders and public. It is necessary to characterize the unknown radioactive dangers produced in the event of these incidents. Advantages to utilizing unmanned aerial systems in this effort are personnel risk reduction and quick attainment of data points in a plume. By pairing a continuous air monitor and detector with a drone, radioactive material concentration can be quantified, and thus the extent of potential doses can be estimated. A small, low-flow air sampler with a Geiger-Mueller counter was characterized using measurements of sources representing a …

Miocene-Quaternary Deformation Along The Central Maynard Lake Fault, Pahranagat Shear Zone, Nevada, Alexander Peck

UNLV Theses, Dissertations, Professional Papers, and Capstones

The left-lateral Pahranagat shear zone (PSZ) and Caliente-Enterprise zone (CEZ) exist at the boundary between two sub-provinces, the Northern (NBR) and Central Basin and Range (CBR). The PSZ contains three major ENE striking sinistral faults, including the Maynard Lake fault (MLF), which is the longest fault and marks the southern boundary of the zone. The PSZ has been suggested to be a transfer zone, but little is known about the structures along these major faults that are involved in strain transfer. These left-lateral systems exist within the Central Nevada seismic belt which has experienced significant earthquakes in recent history. Possible …

Machine Learning Applications In Graduation Prediction At The University Of Nevada, Las Vegas, Elliott Collin Ploutz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Graduation rates of four-year institutions are an increasingly important metric to incoming students and for ranking universities. To increase completion rates, universities must analyze available student data to understand trends and factors leading to graduation. Using predictive modeling, incoming students can be assessed as to their likelihood of completing a degree. If students are predicted to be most likely to drop out, interventions can be enacted to increase retention and completion rates.

At the University of Nevada, Las Vegas (UNLV), four-year graduation rates are 15% and six-year graduation rates are 39%. To improve these rates, we have gathered seven years …

Do I Enact What I Learn?: Examining Novice Science Teachers Approximations Of Practice, Helene Pollins

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to examine novice secondary science teachers’ enactment of their teaching philosophies in their lesson planning and teaching. The framework was based on three theories: approximations of practice, teachers’ knowledge of content and students (KCS), and experiential learning. The design for this research used a qualitative case study design. The participants were three novice science teachers in a large school district in the Southwestern United States. Data sources included teaching philosophies, three semi-structured interviews, lesson plans, and observations. Three research questions were: what are novice science teachers’ major philosophies at the entry level of teaching; …

A Machine Learning Approach To Predict First-Year Student Retention Rates At University Of Nevada, Las Vegas, Aditya Rajuladevi

UNLV Theses, Dissertations, Professional Papers, and Capstones

First-year student retention rates for a four-year institution refers to the percentage of First-time Full-time students from the previous fall who return to the same institution for the following fall. First-year retention rates act as an important indicator of the student satisfaction as well as the performance of the university. Moreover, universities with low retention rates may face a decline in the admissions of talented students with a notable loss of tuition fees and contributions from alumni. Therefore, it is important for universities to formulate strategies to identify students who are at risk of not being retained and take necessary …

A Novel Approach To Analyzing Strain Heterogeneity In Polycrystalline Quartz Specimens Deformed At High Pressure And Temperature, Nolan Ambrose Regis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rheological studies of rocks and minerals allow researchers to study the grain-scale deformation mechanisms that govern large-scale geologic processes from mountain building to mantle mixing. Deforming rock samples with high pressure and temperature apparatuses similar to the Griggs piston cylinder apparatus allows us to simulate deformation at depth. However, many apparatuses are limited to “cook-and-look” analysis and require modeling techniques to determine the evolution of deformation patterns found in experimental samples. A previous study used two-dimensional finite element models to analyze the development of stress and strain patterns in polycrystalline rocks. The study suggested rhythmic patterns in deformed rocks develop …

Primordial Black Holes In The Cosmological Context And Transient Electromagnetic Signatures From Merging Black Hole Binaries, Jared Robert Rice

UNLV Theses, Dissertations, Professional Papers, and Capstones

The cosmological evolution of primordial black holes (PBHs) is presented via analysis of the accretion and evaporation histories of the holes. The ultimate end of any BH is evaporation — a spectacular seconds-long burst of high-energy radiation and particles. The critical initial mass of a PBH undergoing current era evaporation is ∼ 510 trillion grams. A near- critical mass PBH will not accrete radiation or matter in sufficient quantity to retard its inevitable evaporation, if the hole remains within an average volume of the universe. The gravitational waves (GWs) from five BH binary merger events discovered by the LIGO/Virgo collaborations …

Use Of Sodium Bismuthate Chromatography For Separation Of Americium From Curium And Other Elements In Spent Nuclear Fuel, Jason Michael Richards

UNLV Theses, Dissertations, Professional Papers, and Capstones

A novel method for partitioning americium from curium has been developed using sodium bismuthate as both an oxidant and a separation medium. The presence of americium and curium in nuclear waste increases the heat load in geological repositories and leads to larger waste volumes. These elements are also the source of most of the long-term radiotoxicity of the waste. However, the heat load and long-term radiotoxicity contribution from americium is much greater than that from curium. The contribution of curium to the heat load and radiotoxicity of the waste is significant on the same time scale as longer-lived fission products …

Prostate Cancer Survival Among Hispanics: A Surveillance, Epidemiology, And End Results (Seer) Population-Based Cohort Study, David Rivas

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hispanics are now the youngest, largest, and fastest growing minority group in the U.S. Prostate cancer (PC) is the most commonly diagnosed cancer in men and is the second-leading cause of cancer deaths among Hispanics. For the first time, we examined PC-specific survival among distinct Hispanic groups that include Mexicans, Cubans, Dominicans, Puerto Ricans, as well as Central and South Americans. We compared these groups to the main reference population in the U.S., non-Hispanic Whites (NHW), after adjustment for prognostic factor risk categories (prostate-specific antigen (PSA) level, Gleason score, and tumor stage), as well as sociodemographic covariates (e.g., health insurance, …

Solvent Extraction And Extraction Chromatography Of Homologs And Pseudohomologs Of Rutherfordium Using Teha And Tehp, Jeffrey Rolfes

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studies of the chemical properties of the heaviest elements have always been difficult due to the short half-lives and low cross sections involved. To solve this problem, atom-at-a-time methods are necessary to determine the properties of these short-lived isotopes. Extremely fast kinetics for the chemical reactions studied (on the same order as the nuclide’s half-life) are required, and the system should have the potential for automation. Solvent extraction, with its selectivity and quick kinetics, has historically been used for these investigations into characteristics of super heavy elements. Another technique, extraction chromatography, offers potentially a way of investigating rutherfordium’s properties, without …

Applications Of Nanoporous Materials In Gas Separation And Storage, Amit Sharma

UNLV Theses, Dissertations, Professional Papers, and Capstones

Past decades in the field of gas separation and storage utilized the concepts of both cryogenic distillation and non-cryogenic methods such as high-pressure cylinders but few concerns – efficiency, energy intensiveness, cost associated, risk of failure always existed. Recent advances in the field focuses on using porous materials especially nanoporous materials. Nanoporous materials, due to their well-defined structure, range of pore diameters, and striking surface chemistry hold over traditional porous materials for gas separation and storage. With pore diameter less than 2 nm and abundance of energetically favorable sites (such as unsaturated metal sites, channels, cages, cavities etc.), these materials …

Beyond The Bench And The Bedside: Examining Women’S Success In Stem Via Active Learning Projects, Sarah E. Thoman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Gender inequality is a persistent challenge in fields related to science, engineering, technology, and math (STEM) in the U.S. The current study aims to advance the literature in a burgeoning area of inquiry by identifying factors that may help to account for women’s success in STEM. To evaluate STEM success, I used a mixed methods design to investigate STEM identity, career identity status, career commitment, and both individual and situational resilience among women undergraduates. Students were engaged in two project-based STEM programs organized at a large, diverse, research intensive university in the Southwest U.S. Associations between resilience and career commitment, …

Electron Monte Carlo Dose Calculation Model Dependency On Optional Applicator Specific 1d Profiles, Ryan Sharp

UNLV Theses, Dissertations, Professional Papers, and Capstones

The accuracy of a calculated dose distribution compared to the actual dose administered to a patient undergoing electron radiation treatment is dependent upon the configured electron dose calculation algorithm in the treatment planning system (TPS). Configuration of the electron Monte Carlo (eMC) algorithm in the Eclipse TPS requires a variety of beam scan data. One of the required data sets is the inclusion of optional in air crossplane (CP) and inplane (IP) profiles. It is unknown if the inclusion of the optional profiles into the eMC algorithm greatly influences the output of the TPS. Two eMC algorithms were configured in …

An Examination Of The Community And Environmental Impact Of A Las Vegas Convention Food Rescue Program, Samantha H. To

UNLV Theses, Dissertations, Professional Papers, and Capstones

Food insecurity affects millions of Americans each year, inflicting negative consequences on the physical and mental health outcomes at all ages. Concurrently, millions of tons of leftover edible foods are sent to landfill each year. Not only does this pose a question of ethics, but increasingly harms the environment by misusing resources and increasing the release of

greenhouse gases.

Food rescue advisory meetings highlighted the need for more focused research to be conducted that assessed the impacts of donating rescued convention food on local environmental and community health. A mixed-method approach was used to detail the food rescue process between …

Notes On Linear Divisible Sequences And Their Construction: A Computational Approach, Sean Trendell

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this Masters thesis, we examine linear divisible sequences. A linear divisible sequence is any sequence {an}n≥0 that can be expressed by a linear homogeneous recursion relation that is also a divisible sequence. A sequence {an}n≥0 is called a divisible sequence if it has the property that if n|m, then an|am. A sequence of numbers {an}n≥0 is called a linear homogeneous recurrence sequence of order m if it can be written in the form

an+m = p1an+m−1 + p2an+m−2 + · · · + pm−1an+1 + pman, n ≥ 0,

for some constants p1, p2, ..., pm with pm = …

The New Cambrian Children, Shin Watanabe

UNLV Theses, Dissertations, Professional Papers, and Capstones

This MFA thesis is comprised of my collection of poetry entitled The New Cambrian Children. There are fifty-five pages of poetry in this thesis exploring themes of nature, technology, dystopia, and childhood.

Much of the contemporary writing and discussion surrounding the natural world and its relationship with humanity and technology imagines dystopia. There is a tendency to see the world arising from industrialization, computing technologies, and the World Wide Web as a violation of nature and human spirit. This book does not refute this emotional tenor, nor does it claim knowledge of its conclusion. Instead, it forwards conversations between these …

Investigating The Use Of An Emotional Intelligence Intervention With Young Elementary Students Receiving Services In A Self-Contained Setting For Students With Emotional Disturbance, Kristin Lian Withey

UNLV Theses, Dissertations, Professional Papers, and Capstones

While there is a longstanding call for all students to succeed, students receiving special education services under the label of emotional disturbance (ED) are at an increased risk for minimal school and life outcomes, ranging from poor classroom grades and increased expulsion to high rates of incarceration and drug use. Although there are extant interventions, these often rely on extrinsic motivation or are begun after research suggests behaviors have become habit. Because of this, there is a call for earlier intervention that teaches students requisite skills. One such developmentally appropriate practice that has yet to be explored with students receiving …

Design & Delivery Of Automated Winston-Lutz Test For Isocentric & Off-Axis Delivery Stability Utilizing Truebeam Developer Mode & Electronic Portal Imaging Device, Mahmoud Mohammad Yaqoub

UNLV Theses, Dissertations, Professional Papers, and Capstones

The uncertainties in treatment delivery cannot be ignored in radiation therapy. Thus, the quality assurance QA tests are very important task of the medical physicist in clinical practice. Assuring the coincidence between the mechanical isocenter of the Linear Accelerator (LINAC) and its radiation beams isocenter is one of the most important qualities need to be tested, and the Winston Lust (WL) test is the

most popular technique to perform this task, especially for the treatment modalities which need high precision in beam delivery such as the stereotactic radiosurgery/stereotactic body radiotherapy (SRS/SBRT). The linear accelerator-based SRS/SBRT is a well-established method in …

Design On High Performance Nanoscale Cmos Circuits With Low Temperature Sensitivity, Ming Zhu

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the rapid development of integrated circuit (IC) design and manufacturing technology, the transistor size now can be shrunk into only couple of nanometers whereas billions of transistors can be squeezed into a square millimeter, providing unprecedented computation power. However, accompanied with continuous device miniaturization and increased integration density is the explosive growth of on-chip power dissipation and a wide range of temperature fluctuation, which can heavily and negatively affect the delay performance of the circuit, or in the worst case, the circuit may malfunction and the system can be unreliable. Therefore, improved performance resilience against temperature variations has become …

Patellofemoral Joint Stress During Uphill And Downhill Running In Healthy, Theresa French, Brooks Klein, Young Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Subjects: Twenty recreational runners participated (mean age of 24.9 years). Methods: Kinematics and kinetics of the trunk and lower extremity were obtained at 3 conditions: level, 6° uphill, and 6° downhill, at a speed of 2.3 m/s. PFJ stress was determined using a biomechanical model that incorporates knee flexion angle and knee extensor moment as subject-specific input variables. The model output consisted of PFJ reaction force, PFJ stress, and PFJ contact area. One-way ANOVAs with repeated measures and post-hoc t-tests with a Bonferroni adjustment were used to compare outcome variables across the 3 conditions. Results: Peak PFJ stress during downhill …

Golden Arm: A Probabilistic Study Of Dice Control In Craps, Donald R. Smith, Robert Scott Iii

UNLV Gaming Research & Review Journal

This paper calculates how much control a craps shooter must possess on dice outcomes to eliminate the house advantage. A golden arm is someone who has dice control (or a rhythm roller or dice influencer). There are various strategies for dice control in craps. We discuss several possibilities of dice control that would result in several different mathematical models of control. We do not assert whether dice control is possible or not (there is a lack of published evidence). However, after studying casino-legal methods described by dice-control advocates, we can see only one realistic mathematical model that describes the resulting …

The Future Of Construction As It Applies To The Colonization Of The Moon And Mars, Julian Prestia

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goals of this research are:

1. To compile a comprehensive list of all the viable known solutions (and early stage potential solutions) to the issues related to constructing permanent, sustainable, and safe structures for human colonies on our moon and Mars,

2. Determine the most effective potential solutions, and

3. Further develop these ideas as to assist in further space endeavors.

This proposed paper will assist space experts in determining the best next steps in the development of deep-space travel and colonization technologies. Preliminary research has identified several key problems associated with establishing space colonies. They are as follows: …

Enhanced Superconducting Transition Temperature In Electroplated Rhenium, D. P. Pappas, D. E. David, R. E. Lake, M. Bal, R. B. Goldfarb, D. A. Hite, E. Kim, H.-S. Ku, C. R. H. Mcrae, L. D. Pappas, A. Roshko, J. G. Wen, B. L. T. Plourde, I. Arslan, X. Wu

Physics & Astronomy Faculty Research

We show that electroplated Re films in multilayers with noble metals such as Cu, Au, and Pd have an enhanced superconducting critical temperature relative to previous methods of preparing Re. The dc resistance and magnetic susceptibility indicate a critical temperature of approximately 6 K. The magnetic response as a function of field at 1.8 K demonstrates type-II superconductivity, with an upper critical field on the order of 2.5 T. Critical current densities greater than 107 A/m2 were measured above liquid-helium temperature. Low-loss at radio frequency was obtained below the critical temperature for multilayers deposited onto resonators made with Cu traces …

Weaponizing Twitter Litter: Abuse-Forming Networks And Social Media, Hal Berghel

Computer Science Faculty Research

Instead of liberating us from the biases of the educated among us, the Internet has saddled us with the biases of the unreasoned among us.

Innovations International Charter School, Rachel Ugarte

Second-Year Seminar Posters (COE 202)

Innovations International Charter School was built to be a school where students have the resources necessary to academically succeed.

Methylated Dnmt1 And E2f1 Are Targeted For Proteolysis By L3mbtl3 And Crl4dcaf5 Ubiquitin Ligase, Feng Leng, Jiekai Yu, Chunxiao Zhang, Salvador Alejo, Nam Hoang, Hong Sun, Fei Lu, Hui Zhang

Chemistry and Biochemistry Faculty Research

Many non-histone proteins are lysine methylated and a novel function of this modification is to trigger the proteolysis of methylated proteins. Here, we report that the methylated lysine 142 of DNMT1, a major DNA methyltransferase that preserves epigenetic inheritance of DNA methylation patterns during DNA replication, is demethylated by LSD1. A novel methyl-binding protein, L3MBTL3, binds the K142-methylated DNMT1 and recruits a novel CRL4DCAF5 ubiquitin ligase to degrade DNMT1. Both LSD1 and PHF20L1 act primarily in S phase to prevent DNMT1 degradation by L3MBTL3-CRL4DCAF5. Mouse L3MBTL3/MBT-1 deletion causes accumulation of DNMT1 protein, increased genomic DNA methylation, and late embryonic lethality. …

Lagged Influence Of Fine Particulate Matter And Geographic Disparities On Clinic Visits For Children’S Asthma In Taiwan, Lung-Chang Chien, Yu-An Chen, Hwa-Lung Yu

School of Public Health Faculty Research

Recent studies have revealed the influence of fine particulate matter (PM2.5) on increased medication use, hospital admission, and emergency room visits for asthma attack in children, but the lagged influence of PM2.5 on children’s asthma and geographic disparities of children’s asthma have rarely been discussed simultaneously. This study investigated the documented diagnosis of children’s asthma in clinic visits for children aged less than 15 years old that were associated with PM2.5 in two counties located in west-central Taiwan during 2005–2010. The result shows that PM2.5 had a significant lagged effect on children’s asthma for up to 6 days. A significantly …

Reply To 'Anisotropy Governs Strain Stiffening In Nanotwinned-Materials', Bing Li, Hong Sun, Changfeng Chen

Physics & Astronomy Faculty Research

No abstract provided.

Surveillance On The Endemic Of Zika Virus Infection By Meteorological Factors In Colombia: A Population-Based Spatial And Temporal Study, Lung-Chang Chien, Ro-Ting Lin, Yunqi Liao, Francisco S. Sy, Adriana Pérez

School of Public Health Faculty Research

Background Zika virus (ZIKV) infection is a pandemic and a public health emergency. It is transmitted by mosquitoes, primarily the Aedes genus. In light of no treatment currently, it is crucial to develop effective vector control programs to prevent the spread of ZIKV infection earlier when observing possible risk factors, such as weather conditions enhancing mosquito breeding and surviving. Methods This study collected daily meteorological measurements and weekly ZIKV infectious cases among 32 departments of Colombia from January 2015–December 2016. This study applied the distributed lag nonlinear model to estimate the association between the number of ZIKA virus infection and …