Digital Commons Network^™

Mass Determinations Of The Three Mini-Neptunes Transiting Toi-125, Louise D. Nielsen, D. Gandolfi, D. J. Armstrong, J. S. Jenkins, M. Fridlund, N. C. Santos, F. Dai, V. Adibekyan, R. Luque, Jason H. Steffen, M. Esposito, F. Meru, S. Sabotta, E. Bolmont, D. Kossakowski, J. F. Otegi, F. Murgas, M. Stalport, F. Rodler, M. R. Diaz, N. T. Kurtovic, G. Ricker, R. Vanderspek, D. W. Latham, S. Seager, J. N. Winn, J. M. Jenkins, R. Allart, J. M. Almenara, D. Barrado, S. C.C. Barros

Physics & Astronomy Faculty Research

The Transiting Exoplanet Survey Satellite, TESS, is currently carrying out an all-sky search for small planets transiting bright stars. In the first year of the TESS survey, a steady progress was made in achieving the mission’s primary science goal of establishing bulk densities for 50 planets smaller than Neptune. During that year, the TESS’s observations were focused on the southern ecliptic hemisphere, resulting in the discovery of three mini-Neptunes orbiting the star TOI-125, a V = 11.0 K0 dwarf. We present intensive HARPS radial velocity observations, yielding precise mass measurements for TOI-125b, TOI-125c, and TOI-125d. TOI-125b has an orbital period …

Effectively Utilizing Undergraduate Teaching Fellows For Optimal Learning Environment, Patrick Gorman, Meena Barikzi

UNLV Best Teaching Practices Expo

Undergraduate Teaching Fellows focus on working with students in class and outside of class in efforts of boosting confidence in study techniques and learning objectives in the curriculum. Knowing that there is another person who is not only close in age, but in their undergraduate pursuit, provides more comfort in being able to discuss concerns on the coursework. It allows for students to be more active in their academics and promotes an inclusive environment in the classroom. In class, UTFs have the capability of applying creativity in producing lesson plans and activities that allow students to be interactive, allowing for …

Interactive Teaching And Learning, Necole Leland, Karyn Holt

UNLV Best Teaching Practices Expo

Interactive learning is becoming the standard in higher education courses. A primary reason is self-directed constructivist learning employing technology to enhance student learning. Students want to remix what they know with what they just learned to create a broadened knowledge base of their own, directed by themselves, not fed to them by instructors. (Paloff and Pratt, 2013, Marin & Bolliger, 2018). Time efficiency is a second reason interactive learning is a promising practice. By assigning pre-class work, my face to face class time can be used to apply new knowledge rather than introducing it (Educause, 2012). Materials can be provided …

Active Learning Approach For Students In Precalculus And Calculus Classes, Aleksei Talonov

UNLV Best Teaching Practices Expo

We would like to present practices of using Web-based audience response systems to enhance interactive learning activities in Mathematics classroom. We mostly concentrated our attention on PreCalculus classes which have had traditionally low success rates and retention. During the last couple of years, we developed a set of course specific materials in the form of lecture notes and in-class and out-of-class assignments. Each major assignment is accompanied by clear and coherent guidelines explaining what kind of skills will be attained by practicing this assignment, how it can be done, what amount of time can it reasonably take, when is it …

Riesite, A New High Pressure Polymorph Of Tio2 From The Ries Impact Structure, Tschauner, Chi Ma, Antonio Lanzirotti, Matthew G. Newville

Geoscience Faculty Research

This paper describes riesite, a new high-pressure polymorph of TiO2 from the Ries impact structure, Germany. Riesite occurs in shock-induced melt veins within xenoliths of bedrock in suevite. It is structurally closely related to srilankite from which it differs by having two distinct cation sites rather than one and through its monoclinic symmetry. It is indicative that riesite forms only upon release from the shock state upon back transformation from akaogiite.

Towards A Novel Generalized Chinese Remainder Algorithm For Extended Rabin Cryptosystem, Justin Zhan, Peter J. Shiue, Shen C. Huang, Benjamin J. Lowe

Mathematical Sciences Faculty Research

This paper proposes a number of theorems and algorithms for the Chinese Remainder Theorem, which is used to solve a system of linear congruences, and the extended Rabin cryptosystem, which accepts a key composed of an arbitrary finite number of distinct primes. This paper further proposes methods to relax the condition on the primes with trade-offs in the time complexity. The proposed algorithms can be used to provide ciphertext indistinguishability. Finally, this paper conducts extensive experimental analysis on six large data sets. The experimental results show that the proposed algorithms are asymptotically tight to the existing decryption algorithm in the …

Using Hac Estimators For Intervention Analysis, Ashok K. Singh, Rohan J. Dalpatadu

Hospitality Faculty Research

The purpose of this article is to present an alternative method for intervention analysis of time series data that is simpler to use than the traditional method of fitting an explanatory Autoregressive Integrated Moving Average (ARIMA) model. Time series regression analysis is commonly used to test the effect of an event on a time series. An econometric modeling method, which uses a heteroskedasticity and autocorrelation consistent (HAC) estimator of the covariance matrix instead of fitting an ARIMA model, is proposed as an alternative. The method of parametric bootstrap is used to compare the two approaches for intervention analysis. The results …

Author Correction: Closing The Nuclear Fuel Cycle With A Simplified Minor Actinide Lanthanide Separation Process (Alsep) And Additive Manufacturing, Artem V. Gelis, Peter Kozak, Andrew T. Breshears, M. Alex Brown, Cari Launiere, Emily L. Campbell, Gabriel B. Hall, Tatiana G. Levitskaia, Vanessa E. Holfeltz, Gregg J. Lumetta

Chemistry and Biochemistry Faculty Research

No abstract provided.

Finite Element Analysis Of An Arbitrary Lagrangian–Eulerian Method For Stokes/Parabolic Moving Interface Problem With Jump Coefficients, Rihui Lan, Michael J. Ramirez, Pengtao Sun

Mathematical Sciences Faculty Research

In this paper, a type of arbitrary Lagrangian–Eulerian (ALE) finite element method in the monolithic frame is developed for a linearized fluid–structure interaction (FSI) problem — an unsteady Stokes/parabolic interface problem with jump coefficients and moving interface, where, the corresponding mixed finite element approximation in both semi- and fully discrete scheme are developed and analyzed based upon one type of ALE formulation and a novel H1- projection technique associated with a moving interface problem, and the stability and optimal convergence properties in the energy norm are obtained for both discretizations to approximate the solution of a transient Stokes/parabolic interface problem …

Taboo Issue 19.1: Winter 2020, Kenneth J. Fasching-Varner, David Lee Carlson, Andromeda Hightower, Timothy Wells

Taboo: The Journal of Culture and Education

No abstract provided.

Inaccessibility Simulator: Demo Mode, Michaela Stone

Taboo: The Journal of Culture and Education

No abstract provided.

Relation Between Gravitational Mass And Baryonic Mass For Non-Rotating And Rapidly Rotating Neutron Stars, He Gao, Shun-Ke Ai, Zhou-Jian Cao, Bing Zhang, Zhen-Yu Zhu, Ang Li, Nai-Bo Zhang, Andreas Bauswein

Physics & Astronomy Faculty Research

With a selected sample of neutron star (NS) equations of state (EOSs) that are consistent with the current observations and have a range of maximum masses, we investigate the relations between NS gravitational mass Mg and baryonic mass Mb, and the relations between the maximum NS mass supported through uniform rotation (Mmax) and that of nonrotating NSs (MTOV). We find that for an EOS-independent quadratic, universal transformation formula (Mb=Mg+A×M2g)(Mb=Mg+A×Mg2), the best-fit A value is 0.080 for non-rotating NSs, 0.064 for maximally rotating NSs, and 0.073 when NSs with arbitrary rotation are considered. The residual error of the transformation is ∼ …

Buckling Of Blue Phosphorus Nanotubes Under Axial Compression: Insights From Molecular Dynamics Simulations, Shiping Jiang, Huiling Wu, Liangzhi Kou, Chun Tang, Chengyuan Wang, Changfeng Chen

Physics & Astronomy Faculty Research

We report on mechanical properties of blue phosphorus nanotubes (BluePNTs) from systematic molecular dynamics simulations, adopting a Stillinger-Weber potential with parameters determined by fitting to energetic and structural data from first-principles calculations. Our results corroborate the previously reported bending poison effect and size-dependent buckling behaviors. Under axial compression, current simulations predict a shell-to-column buckling mode transition for BluePNTs with increasing aspect ratios; further compression of BluePNTs with large aspect ratios results in a column-to-shell buckling mode transition. Associated critical buckling strains can be described by the continuum mechanics theory. We also simulated buckling behavior of black phosphorus nanotubes (BlackPNTs) and …

A Design Of Mac Model Based On The Separation Of Duties And Data Coloring: Dsdc-Mac, Soon-Book Lee, Yoo-Hwan Kim, Jin-Woo Kim, Chee-Yang Song

Computer Science Faculty Research

Among the access control methods for database security, there is Mandatory Access Control (MAC) model in which the security level is set to both the subject and the object to enhance the security control. Legacy MAC models have focused only on one thing, either confidentiality or integrity. Thus, it can cause collisions between security policies in supporting confidentiality and integrity simultaneously. In addition, they do not provide a granular security class policy of subjects and objects in terms of subjects' roles or tasks. In this paper, we present the security policy of Bell_LaPadula Model (BLP) model and Biba model as …

Page-Net: Interpretable And Integrative Deep Learning For Survival Analysis Using Histopathological Images And Genomic Data, Jie Hao, Sai Chandra Kosaraju, Nelson Zange Tsaku, Dae Hyun Song, Mingon Kang

Computer Science Faculty Research

The integration of multi-modal data, such as histopathological images and genomic data, is essential for understanding cancer heterogeneity and complexity for personalized treatments, as well as for enhancing survival predictions in cancer study. Histopathology, as a clinical gold-standard tool for diagnosis and prognosis in cancers, allows clinicians to make precise decisions on therapies, whereas high-throughput genomic data have been investigated to dissect the genetic mechanisms of cancers. We propose a biologically interpretable deep learning model (PAGE-Net) that integrates histopathological images and genomic data, not only to improve survival prediction, but also to identify genetic and histopathological patterns that cause different …

Wind Power Forecasting Methods Based On Deep Learning: A Survey, Xing Deng, Haijian Shao, Chunlong Hu, Dengbiao Jiang, Yingtao Jiang

Electrical & Computer Engineering Faculty Research

Accurate wind power forecasting in wind farm can effectively reduce the enormous impact on grid operation safety when high permeability intermittent power supply is connected to the power grid. Aiming to provide reference strategies for relevant researchers as well as practical applications, this paper attempts to provide the literature investigation and methods analysis of deep learning, enforcement learning and transfer learning in wind speed and wind power forecasting modeling. Usually, wind speed and wind power forecasting around a wind farm requires the calculation of the next moment of the definite state, which is usually achieved based on the state of …

New Author Guidelines In Statistical Reporting: Embracing An Era Beyond P < .05, Samantha Johnson, Whitley J. Stone, Jennifer Bunn, Scott Lyons, James W. Navalta

Kinesiology and Nutrition Sciences Faculty Research

Statistical reporting of quantitative research data has been plagued by potential bias and reporting suppression due to a single numerical output: the p-value. While there is great importance in its merit, creating a pass-fail system (set at point of .05) has created a culture of researchers submitting their project’s data to a filing cabinet if it does not yield “statistical significance” based on this value. The editors of the International Journal of Exercise Science are following the American Statistical Association’s call for statistical reform by adjusting our reporting guidelines to the following requirements: [1.] make an intentional effort to move …

Games In Agriculture, Food, And Natural Resources Education, Aaron J. Mckim, Robert Bud Mckendree, Catlin M. Pauley

Journal of Research in Technical Careers

Educational games provide learners with team-based, experiential, and problem-centered learning opportunities. Therefore, educational games are recommended to encourage learner success in an increasingly complex and collaborative world. Research exploring interventions to increase teacher affinity toward games is needed to inform expansion of games within classrooms. The current study leveraged the input, environment, and outcomes model to analyze perceptions of games held by school-based agriculture, food, and natural resources (AFNR) educators before and after a professional development experience focused on educational games. Results indicate teachers held a favorable perception of games before engaging in the professional development. Engagement in the professional …

Factors That Influence Persistence Of Biology Majors At A Hispanic-Serving Institution, Shetay Ashford-Hanserd, Kristy Daniel, Dana M. García, Jenn L. Idema

Journal of Research in Technical Careers

To promote diversity within the science, technology, engineering, and mathematics (STEM) workforce, we must identify factors that influence or hinder historically underrepresented minority (URM) students’ persistence to degrees in STEM. We documented potential factors that influence students’ persistence in an undergraduate biology program and created a 14-item, Likert-scale instrument. We recruited 137 undergraduate biology majors at a Hispanic-serving institution in Texas to report which factors they found influential in their decision to remain enrolled in their degree programs. We used a modified social cognitive career theory model of career choice to guide interpretation of the reported influences and identify patterns …

Addressing The Gender Gap: Women’S Perceived Barriers To Pursuing Stem Careers, Marshall Swafford, Ryan Anderson

Journal of Research in Technical Careers

This national study used the Delphi method to identify perceived barriers women face in the pursuit of STEM careers. The study used a series of three web-based questionnaires. The first round of the study used a questionnaire with an open-ended question to facilitate the generation of a wide array of response categories. In round two, respondents were asked to rate the 24 perceived barriers from round one on a Likert-type scale and to make changes as necessary. In round three, respondents were asked to provide a dichotomous indication of whether they agreed or disagreed with each of the items. Consensus …

Mildly Hydrophobic Biobased Mulch: A Sustainable Approach To Controlling Bare Soil Evaporation, Jesse Lee Barnes, Michael John Nicholl

Geoscience Faculty Research

© 2020 The Authors. Vadose Zone Journal published by Wiley Periodicals LLC on behalf of Soil Science Society of America Mulching with polyethylene film is the conventional approach to decrease evaporative water loss from agricultural soils, but it is not environmentally sustainable. In this study, a laboratory experiment was conducted to test the potential utility of partially polymerized soybean oil (PSO) coated sands as a surface treatment to reduce bare soil evaporation. Evaporation was tracked for 23.8 d from saturated sand columns treated with a surface layer (1 or 2 cm) of either coated medium sand (MS-PSO) or coated coarse …

Doctoral Program Design Based On Technology-Based Situated Learning And Mentoring: A Comparison Of Part-Time And Full-Time Doctoral Students, Shaoan Zhang, Chengcheng Li, Mark Carroll, P. G. Schrader

Teaching and Learning Faculty Research

Aim/Purpose Most programs are designed with full-time doctoral students' characteristics and needs in mind; few programs consider the unique needs of part-time doctoral students, including time restrictions, experiences during the program, identity development, and different professional aspirations. The purpose of this study was to evaluate the potential differences between part-time and full-time doctoral students in their scholarly development, and how technology may serve as a communication and organization tool for individual and program support. Background Built on the application of communities of practice, information and communication technology, and situated learning theory, this study sought to evaluate the potential differences among …

A Progressive Output Strategy For Real-Time Feedback Control Systems, Qiming Zou, Ling Wang, Jie Liu, Yingtao Jiang

Electrical & Computer Engineering Faculty Research

The real-time requirements imposed on a feedback control system are often hard to be met, as the controller spends a disproportionately large amount of time waiting for a control cycle to reach its final state. When such a final state is established, multiple tasks have to be prioritized and launched altogether simultaneously, and the system is given an extremely short time window to generate its output. This huge gap between the wait and action times, perceived as a load unbalancing problem, hinders a control decision to be made in real time. To address this challenging problem, in this paper, we …

Dynamic Allocation/Reallocation Of Dark Cores In Many-Core Systems For Improved System Performance, Xingxing Huang, Xiaohang Wang, Yingtao Jiang, Amit Kumar Singh, Mei Yang

Electrical & Computer Engineering Faculty Research

A significant number of processing cores in any many-core systems nowadays and likely in the future have to be switched off or forced to be idle to become dark cores, in light of ever increasing power density and chip temperature. Although these dark cores cannot make direct contributions to the chip's throughput, they can still be allocated to applications currently running in the system for the sole purpose of heat dissipation enabled by the temperature gradient between the active and dark cores. However, allocating dark cores to applications tends to add extra waiting time to applications yet to be launched, …

First-Principles Study Of High-Pressure Phase Stability And Superconductivity Of Bi4i4, Shiyu Deng, Xianqi Song, Quan Li, Yu Xie, Changfeng Chen, Yanming Ma

Physics & Astronomy Faculty Research

Bismuth iodide Bi4I4 exhibits intricate crystal structures and topological insulating states that are highly susceptible to influence by environments, making its physical properties highly tunable by external conditions. In this work, we study the evolution of structural and electronic properties of Bi4I4 at high pressure using an advanced structure search method in conjunction with first-principles calculations. Our results indicate that the most stable ambient-pressure monoclinic α−Bi4I4 phase in C2/m symmetry transforms to a trigonal P31c structure (ɛ−Bi4I4) at 8.4 GPa, then to a tetragonal P4/mmm structure (ζ−Bi4I4) above 16.6 GPa. In contrast to the semiconducting nature of ambient-pressure Bi4I4, the …

Interpretable Deep Neural Network For Cancer Survival Analysis By Integrating Genomic And Clinical Data, Jie Hao, Youngsoon Kim, Tejaswini Mallavarapu, Jung Hun Oh, Mingon Kang

Computer Science Faculty Research

Background: Understanding the complex biological mechanisms of cancer patient survival using genomic and clinical data is vital, not only to develop new treatments for patients, but also to improve survival prediction. However, highly nonlinear and high-dimension, low-sample size (HDLSS) data cause computational challenges to applying conventional survival analysis. Results: We propose a novel biologically interpretable pathway-based sparse deep neural network, named Cox-PASNet, which integrates high-dimensional gene expression data and clinical data on a simple neural network architecture for survival analysis. Cox-PASNet is biologically interpretable where nodes in the neural network correspond to biological genes and pathways, while capturing the nonlinear …

Subglacial Meltwater Supported Aerobic Marine Habitats During Snowball Earth, Maxwell A. Lechte, Malcolm W. Wallace, Ashleig Van Smeerdijk Hooda, Weiqiang Li, Ganqing Jiang, Galen P. Halverson, Dan Asael, Stephanie L. Mccoll, Noah J. Planavsky

Geoscience Faculty Research

The Earth’s most severe ice ages interrupted a crucial interval in eukaryotic evolution with widespread ice coverage during the Cryogenian Period (720 to 635 Ma). Aerobic eukaryotes must have survived the “Snowball Earth” glaciations, requiring the persistence of oxygenated marine habitats, yet evidence for these environments is lacking. We examine iron formations within globally distributed Cryogenian glacial successions to reconstruct the redox state of the synglacial oceans. Iron isotope ratios and cerium anomalies from a range of glaciomarine environments reveal pervasive anoxia in the ice-covered oceans but increasing oxidation with proximity to the ice shelf grounding line. We propose that …

Mojave Desert Ecosystem Recovery: Potency Of Biotic And Abiotic Restoration Methods In Low Elevation Plant Communities, Mary Amanda Balogh

UNLV Theses, Dissertations, Professional Papers, and Capstones

The historic and current state of land in the Mojave Desert, including land managed by the National Park Service with fundamental goals of natural resource conservation and preservation, been severely degraded by a variety of anthropogenic disturbances. Due to increasingly sporadic and unpredictable precipitation patterns, land managers struggle to implement restoration projects with high success rates and are resource-limited for post-treatment monitoring. In this study, I examined success rates of biotic (outplanting, seeding) and abiotic (soil manipulation, vertical mulch) restoration treatments on various disturbance types in the creosote-bursage (Larrea tridentata-Ambrosia dumosa), blackbrush (Coleogyne ramosissima), and Joshua tree woodland (Yucca brevifolia) …

On Muddy Banks: An Ecoethnography Of A River Island Community, Nicholas Baxter

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study, I examine the relationship between a river and a community. Specifically, I analyze the processes and patterns that organize the nature-society relationship and define the river town of Sabula, IA. To guide my historical and ethnographic analysis, I utilize a co constructionist posture (Rice 2013), which sees culture, community, economy, and physicality as much a product of bio-physical forces as social forces. My aim is to understand how Sabula is conjointly constructed and reveal the nuanced interconnections between human communities and nature through which social and environmental problems play out. My analysis clarifies patterns in residents’ identity …

Zirconium Tetrachloride, Fundamental Chemistry And Nuclear Fuel Cycle, Rosendo Borjas Nevarez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zirconium alloys are used in the United States as cladding materials in nuclear reactors. The purification of Zr is of relevance due to the large amount of spent nuclear fuel produced every year (2,000 metric tons per year and rising), of which 25% corresponds to radioactive zirconium cladding. Through the recovery and reuse of Zr, estimated savings of $40 million per year are estimated due to the high cost of hafnium-free nuclear grade zirconium, and also due to the minimization of nuclear waste disposal requirements.

Several chemical approaches have been proposed for the recovery and purification of Zr. Historically, a …