Digital Commons Network^™

Forcing Cesium Into Higher Oxidation States Via Useful Hard X-Ray Induced Chemistry At Extreme Conditions, Daniel Thomas Sneed

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent theoretical work published in Nature Chemistry postulates the existence of cesium in high oxidation states when bonding with fluorine. It is thus predicted to behave as a p-block element (such as xenon) at pressures above 5 GPa. At these pressures, fluorine atoms may bond with the inner p-shell electrons forming CsFn, where n may vary from 2 up to 6; thus the oxidation state of Cs may change up to 6+. My research focused on physically synthesizing these compounds and to verify that, given the right conditions, bonding doesn't only occur with valence electrons, but with the inner p-shell …

A​ Program Evaluation Of Outside Las Vegas’ Ymca Education Program, Robin Mendoza, Kevin Schmidt, Arcelia Barajas, Branson Chun

UNLV Theses, Dissertations, Professional Papers, and Capstones

Today, more than ever, society needs high-quality environmental education programs that succeed in moving values and changing behaviors in the direction of sustainability and conservation. The most common definition of outdoor education comes from "education in, about, and for the outdoors" (Donaldson and Donaldson, 1958, p. 63). They described outdoor learning as taking place “in” the outdoors and the subject matter being “about” nature or the outdoors. There are a variety of studies about “outdoor learning” with a large variation of topics, activities, settings and channels of delivery. The research discussed in this paper will vary slightly to demonstrate the …

The People's College? An Examination Of Who Governs Community Colleges At The Local Level, Katheryn Christine Brekken

UNLV Theses, Dissertations, Professional Papers, and Capstones

Community colleges are playing an increasingly important role in national and local postsecondary education and economic development policy arenas. These two-year institutions educate 46 percent of American undergraduates, including the majority of African American, Hispanic and Native American undergraduate students. However, community colleges are failing to graduate students, particularly students of color (AACC, 2012). Given the national demand for graduates, policymakers are struggling to help more under-represented groups succeed and complete their college degrees. Therefore, an examination of who is governing community colleges and making important policy decisions to address student success is critical. While there are a variety of …

The Validation And Verification Of Les Modeling Using Kiva, David Fyda

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years, the use of large-eddy simulation (LES) has grown into new research methods. LES is preferred when compared to Reynold’s Averaged Navier Stokes (RANS), which separates velocity components into steady and fluctuating components. While RANS is relatively easy to implement, it does not fully resolve the range of turbulence eddies and has limitations that make it inaccurate in many practical circumstances. Direct numerical simulation, DNS, fully resolves all turbulent eddies to the smallest grid scale, but requires an extremely fine grid. This makes it computationally impractical to use as the computational power required to solve even the simplest …

Complex Traffic Network Modeling & Area-Wide Hierarchical Control, Saumya Gupta

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis presents a novel methodology to divide a traffic region into subregions such that in each subregion a Macroscopic Fundamental Diagram (MFD) can be used to determine the state of that subregion. The region division is based on the theory of complex networks. We exploit the inherent network characteristics through PageRank centrality algorithm to identify the most significant nodes in the traffic network. We use these significant nodes as the seeds for a Voronoi diagram based partitioning mechanism of the network. A network wide hierarchical control framework is then presented which controls these sub regions individually and the network …

The San1 Ubiquitin Ligase Functions Preferentially With Ubiquitin-Conjugating Enzyme Ubc1 During Protein Quality Control, Rebeca Lea Ibarra

UNLV Theses, Dissertations, Professional Papers, and Capstones

Protein quality control (PQC) is a critical process wherein misfolded or damaged proteins are cleared from the cell to maintain protein homeostasis. In eukaryotic cells, the removal of misfolded proteins is primarily accomplished by the ubiquitin-proteasome system (UPS). In the UPS, ubiquitin-conjugating enzymes and ubiquitin ligases append poly-ubiquitin chains onto misfolded protein substrates signaling for their degradation. The kinetics of protein ubiquitylation are paramount since a balance must be achieved between the rapid removal of misfolded proteins versus providing sufficient time for protein chaperones to attempt refolding. To uncover the molecular basis for how PQC substrate ubiquitylation rates are controlled, …

Patterns Of Synorogenic Sedimentation Associated With The Unroofing Of The Willard-Paris-Meade Thrust Sheets, Sevier Fold-Thrust Belt, Amanda Gentry

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Willard-Paris-Meade thrust is the oldest and western-most sheet to develop in the Wyoming salient of the Sevier fold-thrust belt. The 10-15 km thick thrust sheet was emplaced ~60 km eastward and included Jurassic-Triassic strata, mixed siliciclastic-carbonate upper Paleozoic strata, carbonate-rich lower Paleozoic strata, and quartzite-rich basal Cambrian to Neoproterozoic strata. Each stratigraphic interval has a distinctive detrital zircon (DZ) age signature, which can be used in provenance analysis of foreland basin fill. The thrust system had a long deformation history recorded by westward thickening and coarsening synorogenic strata. DZ U-Pb geochronology of 27 synorogenic samples collected from two transects …

Investigating Teacher Learning And Change In A Professional Learning Community: Integrating Ela And Social Studies Curriculum, Derek Jordan

UNLV Theses, Dissertations, Professional Papers, and Capstones

This case study examines teacher learning and change in classroom practices as a result of participating in a professional learning community (PLC) that designs integrated curriculum of English/language arts and social studies. The participants for the study were a team of four fifth grade teachers, of which team the author is a member. These teachers teach in a Title-1 urban elementary school in the American Southwest. Case study methodology was chosen to examine this phenomenon. Data were collected from PLC sessions, interviews, recorded lessons, and artifacts. Collection took place at the research site. Data were analyzed using qualitative techniques of …

Incomplete Denitrification In Thermus Species, Chrisabelle Mefferd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Members the bacterial genus Thermus have been shown to be incomplete denitrifiers, terminating with nitrite or nitrous oxide (N2O). However, the ability to carry out denitrification and the evolution of nitrogen oxide reductase genes in Thermus remains poorly understood. This study tests the hypothesis that incomplete denitrification is common in Thermus and seeks to uncover patterns in the evolution of denitrification pathways in Thermus. Denitrification capacity was determined in a collection of 25 strains representing ten species of Thermus and phylogenetic analysis was performed to determine whether denitrification genes evolved horizontally in Thermus. No strains in this study reduced nitrate …

Novel Pathways To High-Efficiency Chalcopyrite Photovoltaic Devices: A Spectroscopic Investigation Of Alternative Buffer Layers And Alkali-Treated Absorbers, Michelle Mezher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Within the past few years, breakthroughs in Cu(In,Ga)Se₂ (CIGSe) thin-film photovoltaic device efficiencies (on a laboratory scale) were achieved utilizing alkali-treated (KF) absorbers. Na incorporation in the CIGSe absorber, either diffused from the substrate or deliberately deposited, affects the surface electronic properties of the CIGSe absorber. The role of Na, however, is still not fully understood with some studies suggesting that Na also passivates defects at the grain boundaries. Replacing Na with K offered an efficiency boost resulting in KF treatments becoming the new “hot topic” in the chalcopyrite field, both in terms of understanding how the treatment changes …

Design, Fabrication And Testing Of Monolithic Low-Power Passive Sigma-Delta Analog-To-Digital Converters, Angsuman Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Analog-to-digital converters are critically important in electronic systems. The

difficulty in meeting high performance parameters increases as integrated circuit design

process technologies advance into the deep nanometer region. Sigma-delta analog-todigital

converters are an attractive option to fulfill many data converter requirements.

These data converters offer high performance while relaxing requirements on the precision

of components within an integrated circuit. Despite this, the active integrators found within

sigma-delta analog-to-digital converters present two main challenges. These challenges are

the power consumption of the active amplifier and achieving gain-bandwidth necessary for

sigma-delta data converters in deep nanometer process technologies. Both of these

challenges …

The Jvmcsp Runtime And Code Generator For Processj In Java, Cabel Dhoj Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

The modern day advancements in multi-core technologies require programmers to use the right tools and languages to fully harness their potentials. On that front, our endeavor lies in developing a new multipro- cessing programming language. Concurrent or parallel programs can be hard to get right because of locks, monitors, mutexes, etc. One solution is using a CSP based process-oriented language. Process-oriented programming alleviates many of the problems found in thread and lock programming by proper encapsu- lation of data, explicit synchronous message passing, and the ability to verify code to be free of deadlocks and livelocks by using tools like …

Development And Testing Of An Assessment To Measure Spatial Thinking About Enhanced Greenhouse Effect, Heather Jean Skaza

UNLV Theses, Dissertations, Professional Papers, and Capstones

Americans, in general, do not behave in environmentally sustainable ways. We drive cars and fly in planes that emit planet-warming carbon. We purchase food in nearly indestructible packaging that is not recycled or repurposed. We do not consider the environmental impact of the “stuff” stuffed into our grocery and department stores, most of which is made of materials that had to be dug out of the ground, leaving rivers and skies full of pollution in its place. Citizens have a responsibility to understand complex global and local environmental problems. A person’s ability to think about the way that an environmental …

Evaluating The Risk To Ostomy Patients Working With Uranium Using The Icrp Biokinetic Model For The Gastrointestinal Tract, Sara Taylor

UNLV Theses, Dissertations, Professional Papers, and Capstones

The ICRP has published two biokinetic models providing a basis for radiation dose assessment due toradionuclides incorporated inside the gastrointestinal tract. These models are a sufficient tool to assess the committed dose equivalent for occupational exposures to workers assuming normal anatomy. The colostomy is becoming a more prevalent procedure. A colostomy permanently or temporarily bypasses a portion of colon to allow rest and healing. There are four different colostomies; ascending, transverse, descending and sigmoid and an ileostomy. As a patient’s strength returns, they can return to normal daily activities, including returning to work. Therefore, as an ostomy patient returns to …

Measurement Of Neutron Activation From A High Energy Varian Linear Accelerator, Timothy Thatcher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Linear accelerators producing photons above 10 MeV may induce photonuclear reactions in high Z components of the accelerator. These liberated neutrons can then activate the structural components of the accelerator and other materials in the beam path through neutron capture reactions. The induced activity within the accelerator may contribute to additional dose to both patients and personnel. This project seeks to determine the total activity and activity per activated isotope following irradiation from a Varian medical linear accelerator at energies above 10 MeV. A Varian 21iX accelerator was used to irradiate a 30 cm x 30 cm x 20 cm …

Structural Evolution Of The Maynard Lake Fault Within The Left-Lateral Pahranagat Shear Zone, Nevada, Usa, Mahmud Mustafa Muhammad

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Pahranagat shear zone (PSZ) contains three ENE-striking left-lateral strike-slip faults: The Arrowhead Mine fault (AMF), Buckhorn fault (BF), and Maynard Lake fault (MLF) from north to south. This shear zone lies along the boundary between the northern and central Basin and Range physiographic sub-provinces (NBR-CBR). In addition, this zone is positioned SW of a regional strike-slip zone, the Caliente-Enterprise zone (CEZ), and surrounded by extensional domains with differences in timing and magnitude of extension. Hence, understanding the development of the PSZ, particularly the MLF, is essential to better understanding tectonic evolution of the boundary zone between the northern and …

Ionic Polymer-Metal Composite Actuators Based On Nafion Blends With Functional Polymers, Jungsoo Nam

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ionic polymer metal composites (IPMCs) have been an attractive research subject for use in underwater robotic applications, biomedical and biomimetic application owing to their great potential as actuators, artificial muscles, and more. IPMC is synthetic composite nanomaterial of ion exchange membranes and metal electrode. Although both components are important, the properties of ion exchange membranes should be emphasized since it is responsible of the path for the mobile ions to migrate when voltage is applied to exhibit deformation. Most of the researches that have been done on IPMCs used commercially available Nafion as their ion exchange membranes. However, its high …

Student Motivation, Stressors, And Intent To Leave A Nursing Phd Or Dnp Program: A National Study Using Path Analysis, Delene Renee Volkert

UNLV Theses, Dissertations, Professional Papers, and Capstones

The growing need for nurse scientists and nurse faculty researchers has led to the call to double the number of doctorally prepared nurses by 2020 (Institute of Medicine [IOM], 2010). Nursing has responded with more doctoral degree programs resulting in an increase from 122 DNP graduates in 2007 to 8,184 nurses who hold DNP degrees by 2013. PhD programs have also seen 5,306 graduates between the years 2004 through 2013 (American Association of Colleges of Nursing [AACN], 2014a). One troubling aspect that affects nursing and other doctoral programs is high attrition rates. A recent ten year longitudinal study from the …

Water Source Partitioning For Shrubland Transpiration In A Mixed Phreatophytic Plant Community, Amanda Jean Wagner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater in the basins of east central Nevada (Great Basin Desert, NV) has been permitted for export to southern Nevada. These basins are also vulnerable to changes in climate that could lead to declining recharge. Any decline in groundwater levels no matter the driving force could significantly impact phreatophytes (deep rooted shrubs), which utilize water from both the vadose zone and the capillary fringe to meet plant water needs, to support growth, and for overall health. A reduction in groundwater due to these forces could have a significant impact on the decoupling of phreatophytes from what is normally a reliable …

Biogeochemistry Of A Saline, Alkaline, Terminal Lake Ecosystem In Transition; Walker Lake, Nevada, Katherine Lynn Willever

UNLV Theses, Dissertations, Professional Papers, and Capstones

Walker Lake is a saline, alkaline, terminal lake ecosystem located in west-central Nevada. For over one hundred years, anthropogenic streamflow diversions within the Walker River Basin have ultimately led to little or no water reaching Walker Lake, the basin’s terminus for water flow. These diversions have resulted in a >46 meter decrease in the lake surface altitude and increases in salinity and dissolved salt constituents that have caused the elimination of native fish species. This study examines how the lack of freshwater inflow has altered the physical, chemical, and microbiological structure of Walker Lake during the lake’s ongoing desiccation.

Between …

Structural Behavior Of Nbsexte2-X Superconductors Under High Pressure, Vahe Mkrtchyan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Niobium chalcogenide compounds have recently gained a great deal of interest due to the fact that a superconducting phase coexists with the charge density wave state (CDW), as well as their potential for numerous applications. Two superconducting compositions, NbSexTe2-x (x=2, 1.5) were prepared by solid state route using high purity Nb, Se, and Te powders. Powder X-ray diffraction patterns collected at ambient conditions for NbSe2 and NbSe1.5Te0.5 showed a single phase with hexagonal crystal structure, with space group P63mmc. High-pressure X-ray diffraction measurements were performed at the Advanced Photon Source at Argonne National Laboratory to investigate structural stability up to …

The Proof Is In The Pots: Residue Analysis Of Virgin Branch Puebloan Ceramics, Brenna Lynn Wilkerson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study focuses on better understanding diet and subsistence strategies among Virgin Branch Puebloan groups living in the Moapa Valley in southern Nevada and on the Shivwits Plateau in northwestern Arizona. Gas chromatography-mass spectrometry (GC-MS) was used to identify absorbed food residues in three types of Virgin Branch Puebloan ceramics (Moapa Gray Ware, Shivwits Ware, and Tusayan Virgin Series). The data produced by the residue analysis were used to compare patterns of subsistence between Virgin Branch Puebloan sites in the lowlands along the Muddy River and at upland sites on the Shivwits Plateau as these two areas have different environments …

Racial And Ethnic Disparities In Dermatology Office Visits Among Insured Patients, 2005-2010, Valerie M. Harvey, Joan Paul, L. Ebony Boulware,

Journal of Health Disparities Research and Practice

Objective:To determine whether differences in race and ethnicity affect the usage of dermatological services.

Methods: Data from the National Ambulatory Medical Care Survey were used to study trends in ethnic/race rates of outpatient dermatology office visits among publicly and privately insured patients from 2005-2010. In multivariable models, we explored the magnitude of ethnic/race differences in dermatology visit attendance for patients with public vs. private insurance.

Results: From 2005-2010, dermatology visit utilization increased among insured Hispanics, but not among insured non-Hispanic Blacks or whites. Visits were less frequent by those with public insurance compared to private insurance. Privately and publicly …

Confessions Of An Unashamed Solution-Focused Purist: What Is (And Isn't) Solution-Focused?, Michael Durrant

Journal of Solution Focused Practices

No abstract provided.

A Hybrid Model Using Logistic Regression And Wavelet Transformation To Detect Traffic Incidents, Shaurya Agarwal, Pushkin Kachroo, Emma Regentova

Electrical & Computer Engineering Faculty Research

This research paper investigates a hybrid model using logistic regression with a wavelet-based feature extraction for detecting traffic incidents. A logistic regression model is suitable when the outcome can take only a limited number of values. For traffic incident detection, the outcome is limited to only two values, the presence or absence of an incident. The logistic regression model used in this study is a generalized linear model (GLM) with a binomial response and a logit link function. This paper presents a framework to use logistic regression and wavelet-based feature extraction for traffic incident detection. It investigates the effect of …

Leading A Horse To Water: Writing Workshops For Engineering Graduate Students, Susan Wainscott, Julie A. Longo

Library Faculty Presentations

A workshop series sponsored by the Howard R. Hughes College of Engineering of the University of Nevada, Las Vegas (UNLV) seeks to dispel the myth that engineers cannot be good writers.

Research On Problem Gambling Websites, Chang Boon Patrick Lee

International Conference on Gambling & Risk Taking

This is a continuation of a series of studies on problem gambling websites. It has been noted in prior studies that one avenue problem gamblers might look for help was to go online to perform a web search. Online help is practical as help can be located immediately and this can help to ease the gamblers’ concerns that they are left alone to handle their own problems. While there are some anecdotal evidences regarding the success of problem gambling websites, there have been few empirical studies that relate directly to the perceptions and usefulness of the websites for the problem …

Optimal Strategy For Gambling Pools, Aaron C. Brown

International Conference on Gambling & Risk Taking

In gambling pools, entrants submit predictions and the prizes are awarded to the prediction or predictions closest to actual outcomes. Some well-known examples are football pools (both the global and American game versions), toto, NCAA March Madness bracket pools and horse racing tournaments. For small pools with complete information about outcome probabilities, exact game theory optimal solutions are straightforward to compute. If there is also complete information about the number and strategy of other players, optimal exploitive strategies are even easier to derive. These problems have been treated in the literature.

This paper argues that the complete information approaches are …

An Empirical Evaluation Of The Clubsnsw (Australia) Multi-Venue Self-Exclusion Program, Dylan A. Pickering, Alexander Blaszczynski, Sally Gainsbury, Rowan Cameron

International Conference on Gambling & Risk Taking

Few empirical studies have evaluated the effectiveness of self-exclusion programs. Research is required to identify factors contributing to decisions to enter and/or breach self-exclusion orders, or to self-excluded gamblers to seek additional treatment. Clinical characteristics of self-excluders remain relatively unknown in addition to factors that differentiate gamblers who do or do not breach. Limitations of current programs are that gamblers can self-exclude from only one or a limited number of venues. The Multi-venue Self-exclusion program, developed and implemented by ClubsNSW (Australia), is a centralised web-based system designed to help problem gamblers self exclude from up to 35 venues at a …

Mandatory Pre-Commitment Loss Limits: Six Years’ Experience Shows It Works, Bjorn H. Hoffmann

International Conference on Gambling & Risk Taking

The Norwegian state owned company Norsk Tipping is a pioneer in the gambling indusrty with its secure player identification and mandatory registered play across all channels. Knowing who your player is and having a strong link between the player and his consumption of games across all channels (land based, EGM, web and mobile) is an important premise for having a credible responsible gaming platform.

Norsk Tipping introduced in 2009 EGM’s with both pre commitment tools and maximum loss limits. In 2014 we introduced our Internet casino with probably the best responsible gambling platform in the world, including mandatory loss limits. …