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Tests Of General Relativity With Gw150914, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following …

Lepton Pair Čerenkov Radiation Emitted By Tachyonic Neutrinos: Lorentz-Covariant Approach And Icecube Data, Ulrich D. Jentschura, Robert B. Ehrlich

Physics Faculty Research & Creative Works

Current experiments do not exclude the possibility that one or more neutrinos are very slightly superluminal or that they have a very small tachyonic mass. Important bounds on the size of a hypothetical tachyonic neutrino mass term are set by lepton pair Čerenkov radiation (LPCR), that is, by the decay channel → e⁺ e^- , which proceeds via a virtual Z⁰ boson. Here, we use a Lorentz-invariant dispersion relation which leads to very tight constraints on the tachyonic mass of neutrinos; we also calculate decay and energy loss rates. A possible cutoff seen in the IceCube neutrino …

Dynamical Mechanisms Leading To Equilibration In Two-Component Gases, Stephan De Bievre, Carlos Mejia-Monasterio, Paul Ernest Parris

Physics Faculty Research & Creative Works

Demonstrating how microscopic dynamics cause large systems to approach thermal equilibrium remains an elusive, longstanding, and actively pursued goal of statistical mechanics. We identify here a dynamical mechanism for thermalization in a general class of two-component dynamical Lorentz gases and prove that each component, even when maintained in a nonequilibrium state itself, can drive the other to a thermal state with a well-defined effective temperature.

Extracting Conformational Structure Information Of Benzene Molecules Via Laser-Induced Electron Diffraction, Yuta Ito, Chuncheng Wang, Anh-Thu Le, Misaki Okunishi, Dajun Ding, C. D. Lin, Kiyoshi Ueda

Physics Faculty Research & Creative Works

We have measured the angular distributions of high energy photoelectrons of benzene molecules generated by intense infrared femtosecond laser pulses. These electrons arise from the elastic collisions between the benzene ions with the previously tunnel-ionized electrons that have been driven back by the laser field. Theory shows that laser-free elastic differential cross sections (DCSs) can be extracted from these photoelectrons, and the DCS can be used to retrieve the bond lengths of gas-phase molecules similar to the conventional electron diffraction method. From our experimental results, we have obtained the C-C and C-H bond lengths of benzene with a spatial resolution …

Privacy-Preserving Controls For Sharing Mhealth Data, Aarathi Prasad

Dartmouth College Ph.D Dissertations

Mobile devices allow people to collect and share health and health-related information with recipients such as health providers, family and friends, employers and insurance companies, to obtain health, emotional or financial benefits. People may consider certain health information sensitive and prefer to disclose only what is necessary. In this dissertation, we present our findings about factors that affect people’s sharing behavior, describe scenarios in which people may wish to collect and share their personal health-related information with others, but may be hesitant to disclose the information if necessary controls are not available to protect their privacy, and propose frameworks to …

Are You Charlie Or Ahmed? Cultural Pluralism In Charlie Hebdo Response On Twitter, Jisun An, Haewoon Kwak, Yelena Mejova, Sonia Alonso Saenz De Oger, Braulio Gomez Fortes

Research Collection School Of Computing and Information Systems

We study the response to the Charlie Hebdo shootings of January 7, 2015 on Twitter across the globe. We ask whether the stances on the issue of freedom of speech can be modeled using established sociological theories, including Huntington’s culturalist Clash of Civilizations, and those taking into consideration social context, including Density and Interdependence theories. We find support for Huntington’s culturalist explanation, in that the established traditions and norms of one’s “civilization” predetermine some of one’s opinion. However, at an individual level, we also find social context to play a significant role, with non-Arabs living in Arab countries using #JeSuisAhmed …

High-Pressure Properties Of Several Narrow Bandgap Semiconductors From First-Principles Calculations, Andrew Michael Alvarado

UNLV Theses, Dissertations, Professional Papers, and Capstones

The electronic, thermodynamic, and structural properties of three semiconducting materials, ZnO, InN, and PbS, at high pressure are investigated utilizing first-principles calculations based on density function theory. The first two systems, ZnO and InN, crystalize as hexagonal structures at ambient conditions and transition to a cubic structure at higher pressures. The last system, PbS, is cubic at ambient conditions, but transitions to an orthorhombic structure at higher pressure. At ambient conditions, these materials are well known semiconductors with vast amount of research and a variety of wide ranging applications in electrical devices. However, there is a lack of understanding of …

Theater Education: Thinking Outside Of The Black Box, Raheve Gray

UNLV Theses, Dissertations, Professional Papers, and Capstones

A 2005 report by the Rand Corporation concluded that "Involvement in the arts is associated with gains in math, reading, cognitive ability, critical thinking, and verbal skill" (Smith). A 2012 report from the National Endowment for the Arts mirrored these findings, stating that “Students who have arts-rich experiences in school do better across-the-board academically, they also become more active and engaged citizens, voting, volunteering, and generally participating at higher rates than their peers” (Garelick 1). The above statements speak to the mounting evidence that arts in education provide extensive benefits for students fortunate enough to have them as part of …

Mcnp6 Computational-Based Sensitivity Propagation Analysis Of Continuous Neutron Cross-Sections Using The Godiva (Hmf-001) And The Godiver (Hmf-004) Benchmark Criticality Study Cases, Lawrence James Lakeotes

UNLV Theses, Dissertations, Professional Papers, and Capstones

There has been a reduction in funding for theoretical and applied research for improving the nation's database of continuous neutron cross-sections at BNL-NNDC. From 1940 through the late 1980s, research and applied development produced volumes of reliable neutron continuous cross-sections for many isotopes. Currently, the cross-section work has been mainly computational. The focus of this research is mainly centered on the requirements for improving thermal cross-sections to support reactor operations and fuel storage. The research efforts will also helpfully aid in the fast fission spectrum in order to support fast reactor designs for improving safety analysis and feedback coefficients.

This …

Neutron-Gamma Discrimination In Elpasolite Scintillator Detector, Brittany Morgan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Existing nuclear stockpiles and weapons-making capabilities imperil the global community. Current nonproliferation efforts involve the research and development of newer, more efficient detection systems that can be deployed for the interdiction and monitoring of special nuclear materials (SNM). Spontaneous and induced fission events in SNM produce neutrons and gamma rays, which can be detected and analyzed, in particular, using scintillator detectors. Various electronic data acquisition systems and data analysis methods have been employed to record and characterize neutron and photon signatures. The goal of this thesis is to develop a new method of discrimination between neutrons and photons in the …

Analysis Of Power-Down Systems With Five States, Govind Pathak

UNLV Theses, Dissertations, Professional Papers, and Capstones

We consider a device, which has states ON, OFF and fixed number of intermediate states.In the ON state the device uses full power whereas in the OFF state the device consumes no energy but a constant cost is associated with switching back to ON. Intermediate states use some fraction of energy proportional to the usage time but switching back to the ON state has a constant setup cost depending on the current state. Such systems are widely used to conserve energy, for example to speed scale CPUs, to control data centers, or to manage renewable energy.

We analyze such a …

A Web-Based Solution For Small Unmanned Aircraft System (Suas) Traffic Management, Monetta Angelique Shaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

There is currently no system in place for safely managing small unmanned aircraft systems (UAS). Small UAS (sUAS) pose a safety hazard to both manned aircraft and people on the ground. The initial solution to this problem proposed in this paper is a system that consists of a web server and an Android mobile application (app). In this solution, the server is only accessible through the Android mobile app. After evaluating the initial solution, we determine that the system in this solution would be unable to quickly adjust to changes in technology and in the sUAS industry. To solve this …

A Web Based User Interface For Machine Learning Analysis Of Health And Education Data, Chandani Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this thesis is to develop a user friendly web application that will be used to analyse data sets using various machine learning algorithms. The application design follows human computer interaction design guidelines and principles to make a user friendly interface [Shn03]. It uses Linear Regression, Logistic Regression, Backpropagation machine learning algorithms for prediction. This application is built using Java, Play framework, Bootstrap and IntelliJ IDE. Java is used in the backend to create a model that maps the input and output data based on any of the above given learning algorithms while Play Framework and Bootstrap are …

Biosynthesis Of Natural And Novel C-Glycosylflavones Utilising Recombinant Oryza Sativa C-Glycosyltransferase (Oscgt) And Desmodium Incanum Root Proteins, B. Hao, J. C. Caulfield, M. L. Hamilton, J. A. Pickett, C. A.O. Midega, Z. R. Khan, J. Wang, A. M. Hooper

All Peer-Reviewed Publications

The rice C-glycosyltransferase (OsCGT) is one of only a small number of characterised plant C-glycosyltransferases (CGT) known. The enzyme C-glucosylates a 2-hydroxyflavanone substrate with UDP-glucose as the sugar donor to produce C-glucosyl-2-hydroxyflavanones. We tested substrate specificity of the enzyme, using synthetic 2-hydroxyflavanones, and showed it has the potential to generate known natural CGFs that have been isolated from rice and also other plants. In addition, we synthesised novel, unnatural 2-hydroxyflavanone substrates to test the B-ring chemical space of substrate accepted by the OsCGT and demonstrated the OsCGT capacity as a synthetic reagent to generate significant quantities of known and novel …

Confronting Williams: The Confrontation Clause And Forensic Witnesses In The Post-Williams Era, Taryn Jones

UC Law Journal

In Williams v. Illinois, the division of the U.S. Supreme Court created substantial confusion as to the proper application of the Confrontation Clause to forensic witnesses. In the decision, the Court affirmed the conviction of the defendant, Sandy Williams, because the plurality and Justice Thomas, in his concurrence, determined that the DNA profile produced by an outside laboratory was not testimonial and thus Williams did not have a constitutional right to crossexamine the laboratory analysts. The plurality and the concurrence, however, presented two distinct rationales for deeming the report nontestimonial. The case has consequently left lower courts without firm guidance …

Expected Worth For 2 × 2 Matrix Games With Variable Grid Sizes, Michael R. Powers, Martin Shubik, Wen Wang

Cowles Foundation Discussion Papers

We offer a detailed examination of a broad class of 2 × 2 matrix games as a first step toward considering measures of resource distribution and efficiency of outcomes. In the present essay, only noncooperative equilibria and entropic outcomes are considered, and a crude measure of efficiency employed. Other solution concepts and the formal construction of an efficiency index will be addressed in a companion paper.

Advances In Repurposing And Recycling Of Post-Vehicle-Application Lithium-Ion Batteries, Charles R. Standridge, Lindsay Corneal, Nicholas Baine

Mineta Transportation Institute

Increased electrification of vehicles has increased the use of lithium-ion batteries for energy storage, and raised the issue of what to do with post-vehicle-application batteries. Three possibilities have been identified: 1) remanufacturing for intended reuse in vehicles; 2) repurposing for non-vehicle, stationary storage applications; and 3) recycling, extracting the precious metals, chemicals and other byproducts. Advances in repurposing and recycling are presented, along with a mathematical model that forecasts the manufacturing capacity needed for remanufacturing, repurposing, and recycling. Results obtained by simulating the model show that up to a 25% reduction in the need for new batteries can be achieved …

Language Teaching In The Secondary Education Classroom: Strategies For Teaching Spanish And English, Alexandria Adair

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This portfolio is a compilation of the author’s beliefs about effectively teaching English as a Second Language and Spanish as a Foreign Language. All of the work in the portfolio centers on the teaching philosophy statement, which contains what the author believes to be the most important aspects of second and foreign language teaching. This statement discusses the importance of communicative language teaching, with a focus on real-life interactions with others. It also advocates teaching content via the second language for more concrete understanding. Four artifacts follow the teaching philosophy statement. The first artifact examines the role of neutral Spanish …

Flight Test Investigation On The Effects Of Aircraft Flap Configuration Change On Longitudinal Trim, Tiziano Bernard

Theses and Dissertations

Loss of Control (LOC) in general aviation has been a topic of extensive study and analysis in the United States and the European Union due to a long series of aircraft accidents in the past decades. The National Transportation Safety Board (NTSB) has identified over 1500 accidents in the traffic pattern involving LOC in general aviation aircraft between 1982 and 2015. LOC has often been attributed to deficiencies in pilot training, and the typical recommendation to reduce the number of accidents is to provide further training in stalls and spins. The European Aviation Safety Agency (EASA) has performed research that …

Cover Crop Mixture Diversity And Function, Angela Florence

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The objective of this study was to evaluate the effect of cover crop mixture diversity on cover crop function. Specifically, this study evaluated the effect of cover crop species and functional richness on aboveground biomass productivity, weed suppression, soil nutrient retention, soil microbial community characteristics, and performance stability. Twenty to forty cover crop treatments were replicated three to four times at eleven sites across southeastern Nebraska using a pool of eighteen species representing three cover crop species each from six pre-defined functional groups: cool-season grasses, cool-season legumes, cool-season brassicas, warm-season grasses, warm-season legumes, and warm-season broadleaves. Each species was planted …

The Joint Effect Of Phenotypic Variation And Temperature On Predator–Prey Interactions, Jean Philippe Gibert

School of Biological Sciences: Dissertations, Theses, and Student Research

Understanding the factors underpinning to food web structure and stability is a long-standing issue in ecology. This is particularly important in a context of global climate change, where rising environmental temperatures may impact the way species interact, potentially leading to changes in food web structure and to secondary extinctions resulting from cascading effects. In order to understand and predict these changes, we need to hone our comprehension on the way predators and their prey interact. Recent studies suggest that, in order to do so, we need to focus on the traits controlling those interactions, such as body size. Mean body …

Impact Of Healthy Food Labels On Consumer Choice And Valuation, Mattingly Perlinger

Department of Agricultural Economics: Dissertations, Theses, and Student Research

The obesity epidemic is prevalent across the entire United States, but minority communities are affected most of all. The Rosebud Indian Reservation in South Dakota is a minority community that has been particularly affected by the obesity epidemic, exhibiting higher rates of obesity and lower life expectancy than the rest of the country.

In this study we conducted a hypothetical choice experiment to test the effectiveness of three healthy food labels in increasing the likelihood of consumers choosing to purchase healthy products. We also calculated the consumer willingness to pay for each of these labels and examined differences in label …

The Assimilation Of Beginning Teachers Into An Established School Improvement Project: A Qualitative Case Study Examining Formats Of Job-Embedded Professional Development, Lynn A. Fuller

Department of Educational Administration: Dissertations, Theses, and Student Research

This dissertation examined formats of job-embedded professional development that were experienced by beginning teachers at a high-poverty, high-mobility elementary school in the third year of a School Improvement Grant. A qualitative case study was conducted to examine formats of job-embedded professional development that were most useful to help beginning teachers assimilate into an established school improvement project and support gains in effective teaching practices and student achievement.

In an effort to define what good teaching is and how we can support it, this study informs education leaders about the power of instructional coaching as a way to provide support and …

Malawi: Orphan Children’S Project, Jasmine A. Lomax

Construction Management

Habitat for Humanity International Global Village recruits and sends volunteers to work on various construction Habitat for Humanity construction projects around the world. The village of Khobili in the Mulanje District of Malawi, Africa was selected as the location to construct three homes for villagers that had lost their homes during severe flooding. For me this was an incredible opportunity to come together with a team of other volunteers to build homes for orphans and their caretaker in a rural Malawian village. The Habitat team worked with skilled local masons to build safe, durable and comfortable houses from the foundation …

Diffusion Modeling And Device Development For Peritoneal Membrane Oxygenation, Liana Hatoum

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Acute respiratory distress syndrome (ARDS) is a pulmonary disease that causes hypoxemia and respiratory failure. The mortality rate for ARDS ranges between 27% and 45%. Current treatments including mechanical ventilation and extracorporeal membrane oxygenation (ECMO) are often associated with high risk complications including barotrauma, infection, thrombosis, and hemorrhage. Alternative pulmonary support techniques are needed to improve the survival rate of patients suffering from ARDS. Previous studies introducing pure O₂ gas, perfluorocarbons and red blood cells into the intraperitoneal (IP) cavity have reported no effect or only a mild increase in oxygenation. Here we report peritoneal membrane oxygenation (PMO) using …

A Pilot Study For Examining Population Movement During The Peri-Medieval Climatic Anomaly In The Nebraska Sand Hills, Nora C. Greiman

Department of Anthropology: Theses and Student Research

The Sand Hills of Nebraska comprise a dynamic environment of sand dunes that has changed much over the millennia since their formation. Periods of dune reactivation have occurred throughout history, including one such period at approximately A.D. 900-1300 associated with the Medieval Climatic Anomaly (MCA). Much is known about the geologic activity during this period but little is known about how human populations responded to changing environments. I examine the chronology of three sites occupied during the peri-MCA and the change or stasis in population movements via chemical characterization of ceramic artifacts. Optically stimulated luminescence (OSL) dating was performed on …

Charge Collection Kinetics On Ferroelectric Polymer Surface Using Charge Gradient Microscopy, Yoon-Young Choi, Sheng Tong, Stephen Ducharme, Andreas Roelofs, Seungbum Hong

Stephen Ducharme Publications

A charge gradient microscopy (CGM) probe was used to collect surface screening charges on poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] thin films. These charges are naturally formed on unscreened ferroelectric domains in ambient condition. The CGM data were used to map the local electric current originating from the collected surface charges on the poled ferroelectric domains in the P(VDF-TrFE) thin films. Both the direction and amount of the collected current were controlled by changing the polarity and area of the poled domains. The endurance of charge collection by rubbing the CGM tip on the polymer film was limited to 20 scan cycles, after …

Adult Hispanic Students' Attitudes Toward Writing In English In A U.S. Bilingual Community, Analynn Bustamante

Theses and Dissertations

Attitude is widely regarded as a key component for writing achievement. This study explores the relationship between students’ language dominance and their attitudes toward writing in English. Seventy-seven Hispanic adult students were recruited to participate in a survey. Four writing domains were tested: writing in general, writing in STEM courses, writing in humanities courses and writing in electronic communication. Participants’ attitudes toward four different writing domains were compared. Significant difference was found between attitudes toward general writing attitudes and attitudes toward writing STEM courses, as well as between general writing and writing in humanities courses. Additionally, participants were divided by …

Comunicando Emociones: Language Preferences For Hispanics In The Rio Grande Valley, Elim Hernandez

Theses and Dissertations

According to the U.S Census Bureau, more than one million Hispanic or Latino individuals live in the southernmost area of Texas called The Rio Grande Valley (RGV). However, being Hispanic in the RGV does not mean you speak Spanish. In fact, most of the population speaks English and/or Spanish or “Spanglish” (Tex-Mex). As a result, individuals face code-switching (switching back and forth in two languages) when they communicate with one another. Which language do they prefer to express their emotions in? The study posed a research question along this line. Nine college students who met the research criteria were interviewed …

11th New World Luminescence Dating Workshop Scientific Program And Abstracts And Field Trip Guide Book, P.R. Hanson, James B. Swinehart, Joseph Mason

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.