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Articles 571 - 600 of 3930

Full-Text Articles in Physical Sciences and Mathematics

Initial Measurements On The Effect Of Stress On P- And S-Wave Velocities In Olivine, Taryn Traylor Dec 2020

Initial Measurements On The Effect Of Stress On P- And S-Wave Velocities In Olivine, Taryn Traylor

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is well known that elasticity is a key physical property in the determination of the structure and composition of the Earth and provides critical information for the interpretation of seismic data. This study investigates the stress-induced variation in elastic wave velocities, known as the acoustoelastic effect, in San Carlos olivine. A recently developed experimental ultrasonic acoustic system, the Directly Integrated Acoustic System Combined with Pressure Experiments (DIASCoPE), was used with the D-DIA multi-anvil apparatus to transmit ultrasonic sound waves and collect the reflections. We use the DIASCoPE to obtain longitudinal (P) and shear (S) elastic wave velocities from the …

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Shakespeare’S As You Like It And James Cameron’S Avatar: Reharmonizing Society With Nature, Erin Rebecca Turner Dec 2020

Shakespeare’S As You Like It And James Cameron’S Avatar: Reharmonizing Society With Nature, Erin Rebecca Turner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shakespeare’s As You Like It is a comedy whose main character, Rosalind, is forced out of her home among the upper caste of society through no fault of her own, but because of an issue with her father. She moves into the pastoral unknown disguised as a man to avoid the issues that come traveling as a woman, outside the protection of the home. Along the way, she finds pleasure with the power she holds as a man. She is heard when she speaks as a man and she is given access to knowledge she would not be given as …

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An Exploration Of The Numeracy Skills Required For Safe, Quality Nursing Practice, Anna Wendel Dec 2020

An Exploration Of The Numeracy Skills Required For Safe, Quality Nursing Practice, Anna Wendel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to explore the numeracy skills required for safe, quality nursing practice. Using a descriptive mixed methods design, this study answered two research questions: 1) What numeracy skills do nurses perceive as important for providing safe, quality nursing care in the first three years of practice? 2) How do nurses incorporate numeracy skills into daily patient care during the first three years of practice? Early career nurses from a not-for-profit health care organization in the mid-Atlantic region of the United States (n=109) responded to an online survey tool developed by the student investigator that ranked …

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Equivalences Of Determinacy Between Levels Of The Borel Hierarchy And Long Games, And Some Generalizations, Katherine Aimee Yost Dec 2020

Equivalences Of Determinacy Between Levels Of The Borel Hierarchy And Long Games, And Some Generalizations, Katherine Aimee Yost

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis will be primarily focused on directly proving that the determinacy of Borel games in X^ω is equivalent to the determinacy of certain long open games, from a fragment of ZFC that’s well-known to be insufficient to prove Borel determinacy. The main theorem is a level by level result which shows the equivalence between determinacy of open games in a long tree, [Υ^α], and determinacy of Σ_0^α games in X^ω. In Chapter 9, we mimic the proof used in our main theorem to show that the determinacy of clopen games in the product space X^ω × ω^ω is equivalent …

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Developments Of Machine Learning Potentials For Atomistic Simulations, Howard Yanxon Dec 2020

Developments Of Machine Learning Potentials For Atomistic Simulations, Howard Yanxon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Atomistic modeling methods such as molecular dynamics play important roles in investigating time-dependent physical and chemical processes at the microscopic level. In the simulations, energy and forces, sometimes including stress tensor, need to be recalculated iteratively as the atomic configuration evolves. Consequently, atomistic simulations crucially depend on the accuracy of the underlying potential energy surface. Modern quantum mechanical modeling based on density functional theory can consistently generate an accurate description of the potential energy surface. In most cases, molecular dynamics simulations based on density functional theory suffer from highly demanding computational costs. On the other hand, atomistic simulations based on …

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Response Of The Mode Grüneisen Parameters With Anisotropic Compression: A Pressure And Temperature Dependent Raman Study Of Β-Sn, Jasmine K. Hinton, Christian Childs, Dean Smith, Paul B. Ellison, Keith V. Lawler, Ashkan Salamat Nov 2020

Response Of The Mode Grüneisen Parameters With Anisotropic Compression: A Pressure And Temperature Dependent Raman Study Of Β-Sn, Jasmine K. Hinton, Christian Childs, Dean Smith, Paul B. Ellison, Keith V. Lawler, Ashkan Salamat

Physics & Astronomy Faculty Research

The lattice dynamic response of body-centered tetragonal β−Sn (I41/amd) under high pressure and -temperature conditions is determined using experimental optical vibration modes. Raman scattering is used to map the phase stability region of β−Sn to perform mode Grüneisen analysis, and we demonstrate the necessity of an optical intensity calibration for Raman thermometry. The Grüneisen tensor is evaluated along a set of isotherms to address shortcomings of single-mode Grüneisen parameters with respect to anisotropic deformations of this tetragonal structured soft metal. The changes observed here in the Grüneisen tensor as a function of temperature are related to anharmonicity and denote potential …

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What Martian Meteorites Reveal About The Interior And Surface Of Mars, Arya Udry, G. H. Howarth, C. D.K. Herd, J. M.D. Day, T. J. Lapen, J. Filiberto Nov 2020

What Martian Meteorites Reveal About The Interior And Surface Of Mars, Arya Udry, G. H. Howarth, C. D.K. Herd, J. M.D. Day, T. J. Lapen, J. Filiberto

Geoscience Faculty Research

Martian meteorites are the only direct samples from Mars, thus far. Currently, there are a total of 262 individual samples originating from at least 11 ejection events. Geochemical analyses, through techniques that are also used on terrestrial rocks, provide fundamental insights into the bulk composition, differentiation and evolution, mantle heterogeneity, and role of secondary processes, such as aqueous alteration and shock, on Mars. Martian meteorites display a wide range in mineralogy and chemistry, but are predominantly basaltic in composition. Over the past 6 years, the number of martian meteorites recovered has almost doubled allowing for studies that evaluate these meteorites …

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Potential Application Of Ionic Liquids For Electrodeposition Of The Material Targets For Production Of Diagnostic Radioisotopes, Maciej Chotkowski, Damian Połomski, Kenneth Czerwinski Nov 2020

Potential Application Of Ionic Liquids For Electrodeposition Of The Material Targets For Production Of Diagnostic Radioisotopes, Maciej Chotkowski, Damian Połomski, Kenneth Czerwinski

Chemistry and Biochemistry Faculty Research

An overview of the reported electrochemistry studies on the chemistry of the element for targets for isotope production in ionic liquids (ILs) is provided. The majority of investigations have been dedicated to two aspects of the reactive element chemistry. The first part of this review presents description of the cyclotron targets properties, especially physicochemical characterization of irradiated elements. The second part is devoted to description of the electrodeposition procedures leading to obtain elements or their alloys coatings (e.g., nickel, uranium) as the targets for cyclotron and reactor generation of the radioisotopes. This review provides an evaluation of the role ILs …

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The Evolution Of A Circumplanetary Disc With A Dead Zone, Cheng Chen, Chao Chin Yang, Rebecca G. Martin, Zhaohuan Zhu Nov 2020

The Evolution Of A Circumplanetary Disc With A Dead Zone, Cheng Chen, Chao Chin Yang, Rebecca G. Martin, Zhaohuan Zhu

Physics & Astronomy Faculty Research

© 2021 Oxford University Press. All rights reserved. We investigate whether the regular Galilean satellites could have formed in the dead zone of a circumplanetary disc. A dead zone is a region of weak turbulence in which the magnetorotational instability is suppressed, potentially an ideal environment for satellite formation. With the grid-based hydrodynamic code FARGO3D, we examine the evolution of a circumplanetary disc model with a dead zone. Material accumulates in the dead zone of the disc leading to a higher total mass and but a similar temperature profile compared to a fully turbulent disc model. The tidal torque increases …

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Lead Complexation By Humic Acids And Their Analogs: A Voltammetric Study, Spencer Steinberg, Vernon Hodge Nov 2020

Lead Complexation By Humic Acids And Their Analogs: A Voltammetric Study, Spencer Steinberg, Vernon Hodge

Chemistry and Biochemistry Faculty Research

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Differential pulse polarography (DPP) was used to assess the interaction of Pb2+ with various humic acid analogs and several humic acids. DPP analysis demonstrated that the reduction peak maximum (Ep) for Pb2+ shifted to more negative values in the presence of humic acids and humic acid analogs. The observed Ep for Pb2+ in the presence of humic acids and humic acid analogs is influenced by ligand concentration, solution pH and Pb2+ concentration. Shifts in the Ep for Pb2+ are related to the reduction potential and can be rationalized using the Lingane …

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Radiological Identification Of Near‐Surface Mineralogical Deposits Using Low‐Altitude Unmanned Aerial Vehicle, Peter G. Martin, Dean T. Connor, Natalia Estrada, Adel El-Turke, David Megson-Smith, Chris P. Jones, David K. Kreamer, Thomas B. Scott Oct 2020

Radiological Identification Of Near‐Surface Mineralogical Deposits Using Low‐Altitude Unmanned Aerial Vehicle, Peter G. Martin, Dean T. Connor, Natalia Estrada, Adel El-Turke, David Megson-Smith, Chris P. Jones, David K. Kreamer, Thomas B. Scott

Geoscience Faculty Research

An ever‐increasing global population and unabating technological growth have resulted in a relentless appetite for mineral resources, namely rare earth elements, fuel minerals and those utilised in electronics applications, with the price of such species continuing to climb. In contrast to more established large‐scale and high‐cost exploration methodologies, this work details the application of novel multi‐rotor unmanned aerial vehicles equipped with miniaturised radiation detectors for the objective of undertaking resource exploration at lower costs, with greater autonomy and at considerably enhanced higher spatial resolutions; utilizing the ore material’s inherent low levels of characteristic radioactivity. As we demonstrate at the former …

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Xenon Iron Oxides Predicted As Potential Xe Hosts In Earth’S Lower Mantle, Feng Peng, Xianqi Song, Chang Liu, Quan Li, Maosheng Miao, Changfeng Chen, Yanming Ma Oct 2020

Xenon Iron Oxides Predicted As Potential Xe Hosts In Earth’S Lower Mantle, Feng Peng, Xianqi Song, Chang Liu, Quan Li, Maosheng Miao, Changfeng Chen, Yanming Ma

Physics & Astronomy Faculty Research

An enduring geological mystery concerns the missing xenon problem, referring to the abnormally low concentration of xenon compared to other noble gases in Earth’s atmosphere. Identifying mantle minerals that can capture and stabilize xenon has been a great challenge in materials physics and xenon chemistry. Here, using an advanced crystal structure search algorithm in conjunction with first-principles calculations we find reactions of xenon with recently discovered iron peroxide FeO2, forming robust xenon-iron oxides Xe2FeO2 and XeFe3O6 with significant Xe-O bonding in a wide range of pressure-temperature conditions corresponding to vast regions in Earth’s lower mantle. Calculated mass density and sound …

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Countercurrent Actinide Lanthanide Separation Process (Alsep) Demonstration Test With A Simulated Purex Raffinate In Centrifugal Contactors On The Laboratory Scale, Andreas Wilden, Fabian Kreft, Dimitri Schneider, Zaina Paparigas, Giuseppe Modolo, Gregg J. Lumetta, Artem V. Gelis, Jack D. Law, Andreas Geist Oct 2020

Countercurrent Actinide Lanthanide Separation Process (Alsep) Demonstration Test With A Simulated Purex Raffinate In Centrifugal Contactors On The Laboratory Scale, Andreas Wilden, Fabian Kreft, Dimitri Schneider, Zaina Paparigas, Giuseppe Modolo, Gregg J. Lumetta, Artem V. Gelis, Jack D. Law, Andreas Geist

Chemistry and Biochemistry Faculty Research

An Actinide Lanthanide Separation Process (ALSEP) for the separation of trivalent actinides (An(III)) from simulated raffinate solution was successfully demonstrated using a 32-stage 1 cm annular centrifugal contactor setup. The ALSEP solvent was composed of a mixture of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) and N,N,N′,N′-tetra-(2-ethylhexyl)-diglycolamide (T2EHDGA) in n-dodecane. Flowsheet calculations and evaluation of the results were done using the Argonne’s Model for Universal Solvent Extraction (AMUSE) code using single-stage distribution data. The co-extraction of Zr(IV) and Pd(II) was prevented using CDTA (trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid) as a masking agent in the feed. For the scrubbing of co-extracted Mo; citrate-buffered acetohydroxamic acid was …

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Toughening A Superstrong Carbon Crystal: Sequential Bond-Breaking Mechanisms, Hui Liang, Hefei Li, Quan Li, Changfeng Chen Oct 2020

Toughening A Superstrong Carbon Crystal: Sequential Bond-Breaking Mechanisms, Hui Liang, Hefei Li, Quan Li, Changfeng Chen

Physics & Astronomy Faculty Research

A complex orthorhombic carbon allotrope in Pbam symmetry with 32 atoms in its unit cell, thus termed Pbam-32 carbon, was recently predicted [C. Y. He et al., Phys. Rev. Lett. 121, 175701 (2018)]. Its crystal structure comprises alternating fivefold, sixfold, and sevenfold carbon rings and exhibits reduced bonding anisotropy compared to diamond, raising the prospects of finding a superstrong material with distinct and favorable mechanical properties. Here we report findings from first-principles calculations that reveal peculiar stress-strain relations in Pbam-32 carbon. The obtained stress responses under various tensile and shear strains display outstanding characteristics contrasting those of traditional superhard materials …

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A Thousand Days After The Merger: Continued X-Ray Emission From Gw170817, E. Troja, H. Van Eerten, Bing Zhang, G. Ryan, L. Piro, R. Ricci, B. O'Connor, M. H. Wieringa, S. B. Cenko, T. Sakamoto Oct 2020

A Thousand Days After The Merger: Continued X-Ray Emission From Gw170817, E. Troja, H. Van Eerten, Bing Zhang, G. Ryan, L. Piro, R. Ricci, B. O'Connor, M. H. Wieringa, S. B. Cenko, T. Sakamoto

Physics & Astronomy Faculty Research

Recent observations with the Chandra X-ray telescope continue to detect X-ray emission from the transient GW170817. In a total exposure of 96.6 ks, performed between 2020 March 9 and 16 (935–942 d after the merger), a total of 8 photons are measured at the source position, corresponding to a significance of ≈5σ. Radio monitoring with the Australian Telescope Compact Array (ATCA) shows instead that the source has faded below our detection threshold... (See full abstract in article).

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Recent Advancements In The Removal Of Cyanotoxins From Water Using Conventional And Modified Adsorbents—A Contemporary Review, Tauqeer Abbas, George William Kajjumba, Meena Ejjada, Sayeda Ummeh Masrura, Erica J. Marti, Eakalak Khan, Tammy L. Jones-Lepp Oct 2020

Recent Advancements In The Removal Of Cyanotoxins From Water Using Conventional And Modified Adsorbents—A Contemporary Review, Tauqeer Abbas, George William Kajjumba, Meena Ejjada, Sayeda Ummeh Masrura, Erica J. Marti, Eakalak Khan, Tammy L. Jones-Lepp

Civil and Environmental Engineering and Construction Faculty Research

The prevalence of cyanobacteria is increasing in freshwaters due to climate change, eutrophication, and their ability to adapt and thrive in changing environmental conditions. In response to various environmental pressures, they produce toxins known as cyanotoxins, which impair water quality significantly. Prolonged human exposure to cyanotoxins, such as microcystins, cylindrospermopsin, saxitoxins, and anatoxin through drinking water can cause severe health effects. Conventional water treatment processes are not effective in removing these cyanotoxins in water and advanced water treatment processes are often used instead. Among the advanced water treatment methods, adsorption is advantageous compared to other methods because of its affordability …

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Rethinking The Weakness Of Stream Ciphers And Its Application To Encrypted Malware Detection, William Stone, Daeyoung Kim, Victor Youdom Kemmoe, Mingon Kang, Junggab Son Oct 2020

Rethinking The Weakness Of Stream Ciphers And Its Application To Encrypted Malware Detection, William Stone, Daeyoung Kim, Victor Youdom Kemmoe, Mingon Kang, Junggab Son

Computer Science Faculty Research

One critical vulnerability of stream ciphers is the reuse of an encryption key. Since most stream ciphers consist of only a key scheduling algorithm and an Exclusive OR (XOR) operation, an adversary may break the cipher by XORing two captured ciphertexts generated under the same key. Various cryptanalysis techniques based on this property have been introduced in order to recover plaintexts or encryption keys; in contrast, this research reinterprets the vulnerability as a method of detecting stream ciphers from the ciphertexts it generates. Patterns found in the values (characters) expressed across the bytes of a ciphertext make the ciphertext distinguishable …

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Pressure-Stabilized Divalent Ozonide Cao3 And Its Impact On Earth’S Oxygen Cycles, Yanchao Wang, Meiling Xu, Liuxiang Yang, Bingmin Yan, Qin Qin, Xuecheng Shao, Yunwei Zhang, Dajian Huang, Xiaohuan Lin, Jian Lv, Dongzhou Zhang, Huiyang Gou, Ho-Kwang Mao, Changfeng Chen, Yanming Ma Sep 2020

Pressure-Stabilized Divalent Ozonide Cao3 And Its Impact On Earth’S Oxygen Cycles, Yanchao Wang, Meiling Xu, Liuxiang Yang, Bingmin Yan, Qin Qin, Xuecheng Shao, Yunwei Zhang, Dajian Huang, Xiaohuan Lin, Jian Lv, Dongzhou Zhang, Huiyang Gou, Ho-Kwang Mao, Changfeng Chen, Yanming Ma

Physics & Astronomy Faculty Research

High pressure can drastically alter chemical bonding and produce exotic compounds that defy conventional wisdom. Especially significant are compounds pertaining to oxygen cycles inside Earth, which hold key to understanding major geological events that impact the environment essential to life on Earth. Here we report the discovery of pressure-stabilized divalent ozonide CaO3 crystal that exhibits intriguing bonding and oxidation states with profound geological implications. Our computational study identifies a crystalline phase of CaO3 by reaction of CaO and O2 at high pressure and high temperature conditions; ensuing experiments synthesize this rare compound under compression in a diamond anvil cell with …

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Measuring The Perceived Social Intelligence Of Robots, Kimberly A. Barchard, Leiszle Lapping-Carr, R. Shane Westfall, Andrea Fink-Armold, Santosh Balajee Banisetty, David Feil-Seifer Sep 2020

Measuring The Perceived Social Intelligence Of Robots, Kimberly A. Barchard, Leiszle Lapping-Carr, R. Shane Westfall, Andrea Fink-Armold, Santosh Balajee Banisetty, David Feil-Seifer

Psychology Faculty Research

Robotic social intelligence is increasingly important. However, measures of human social intelligence omit basic skills, and robot-specific scales do not focus on social intelligence. We combined human robot interaction concepts of beliefs, desires, and intentions with psychology concepts of behaviors, cognitions, and emotions to create 20 Perceived Social Intelligence (PSI) Scales to comprehensively measure perceptions of robots with a wide range of embodiments and behaviors. Participants rated humanoid and non-humanoid robots interacting with people in five videos. Each scale had one factor and high internal consistency, indicating each measures a coherent construct. Scales capturing perceived social information processing skills (appearing …

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Resilience And Alternative Stable States After Desert Wildfires, Scott R. Abella, Dominic M. Gentilcore, Lindsay P. Chiquoine Sep 2020

Resilience And Alternative Stable States After Desert Wildfires, Scott R. Abella, Dominic M. Gentilcore, Lindsay P. Chiquoine

Life Sciences Faculty Research

Improving models of community change is a fundamental goal in ecology and has renewed importance during global change and increasing human disturbance of the biosphere. Using the Mojave Desert (southwestern United States) as a model system, invaded by nonnative plants and subject to wildfire disturbances, we examined models of resilience, alternative stable states, and convergent-divergent trajectories for 36 yr of plant community change after 31 wildfires in communities dominated by the native shrubs Larrea tridentata or Coleogyne ramosissima. Perennial species richness on average was fully resilient within 23 yr after disturbance in both community types. Perennial cover was fully resilient …

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Investigation Of The Interaction Of Gadolinium With Several Organic Ligands And Humic Acid By Ligand Competition Using 4-(2-Pyridylazo)-Resorcinol (Par), Spencer Steinberg, Vernon Hodge, Luis Becerra-Hernandez Sep 2020

Investigation Of The Interaction Of Gadolinium With Several Organic Ligands And Humic Acid By Ligand Competition Using 4-(2-Pyridylazo)-Resorcinol (Par), Spencer Steinberg, Vernon Hodge, Luis Becerra-Hernandez

Chemistry and Biochemistry Faculty Research

Gd3+ forms a strongly colored complex with 4-(2-pyridylazo)-resorcinol (PAR) in aqueous solutions. We characterized the Gd3+-PAR complex in order to use it as a probe of Gd3+ speciation in the presence of environmentally relevant ligands. The formation of the Gd3+-PAR complex was investigated from pH 5 to 8 in the presence of excess PAR. The absorbance of the Gd3+-PAR complex dramatically increased from pH 5 to 8 and application of the method of continuous variation indicates that the complex was primarily 1:2 Gd(PAR)2 at pH 8. Stability constants for Gd3+ with other ligands can be quantified by competitive displacement of …

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Future Availability Of Non-Renewable Metal Resources And The Influence Of Environmental, Social, And Governance Conflicts On Metal Production, Simon Jowitt, Gavin M. Mudd, John F.H. Thompson Sep 2020

Future Availability Of Non-Renewable Metal Resources And The Influence Of Environmental, Social, And Governance Conflicts On Metal Production, Simon Jowitt, Gavin M. Mudd, John F.H. Thompson

Geoscience Faculty Research

Metal mining provides the elements required for the provision of energy, communication, transport and more. The increasing uptake of green technology, such as electric vehicles and renewable energy, will also further increase metal demand. However, the production lifespan of an average mine is far shorter than the timescales of mineral deposit formation, suggesting that metal mining is unsustainable on human timescales. In addition, some research suggests that known primary metal supplies will be exhausted within about 50 years. Here we present an analysis of global metal reserves that suggests that primary metal supplies will not run out on this timescale. …

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Measuring The Perceived Social Intelligence Of Robots, Kimberly A. Barchard, Leiszle Lapping-Carr, R. Shane Westfall, Andrea Fink-Armold, Santosh Balajee Banisetty, David Feil-Seifer Sep 2020

Measuring The Perceived Social Intelligence Of Robots, Kimberly A. Barchard, Leiszle Lapping-Carr, R. Shane Westfall, Andrea Fink-Armold, Santosh Balajee Banisetty, David Feil-Seifer

Psychology Faculty Research

Robotic social intelligence is increasingly important. However, measures of human social intelligence omit basic skills, and robot-specific scales do not focus on social intelligence. We combined human robot interaction concepts of beliefs, desires, and intentions with psychology concepts of behaviors, cognitions, and emotions to create 20 Perceived Social Intelligence (PSI) Scales to comprehensively measure perceptions of robots with a wide range of embodiments and behaviors. Participants rated humanoid and non-humanoid robots interacting with people in five videos. Each scale had one factor and high internal consistency, indicating each measures a coherent construct. Scales capturing perceived social information processing skills (appearing …

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Machine Learning Corrected Quantum Dynamics Calculations, A. Jasinski, J. Montaner, R. C. Forrey, B. H. Yang, P. C. Stancil, Naduvalath Balakrishnan, J. Dai, A. Vargas-Hernandez, R. V. Krems Aug 2020

Machine Learning Corrected Quantum Dynamics Calculations, A. Jasinski, J. Montaner, R. C. Forrey, B. H. Yang, P. C. Stancil, Naduvalath Balakrishnan, J. Dai, A. Vargas-Hernandez, R. V. Krems

Chemistry and Biochemistry Faculty Research

Quantum scattering calculations for all but low-dimensional systems at low energies must rely on approximations. All approximations introduce errors. The impact of these errors is often difficult to assess because they depend on the Hamiltonian parameters and the particular observable under study. Here, we illustrate a general, system- and approximation-independent, approach to improve the accuracy of quantum dynamics approximations. The method is based on a Bayesian machine learning (BML) algorithm that is trained by a small number of exact results and a large number of approximate calculations, resulting in ML models that can generalize exact quantum results to different dynamical …

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Toluene Induces Hormetic Response Of Soil Alkaline Phosphatase And The Potential Enzyme Kinetic Mechanism, Diwu Fan, Yujing Jing, Yongli Zhu, Sajjad Ahmad, Jiangang Han Aug 2020

Toluene Induces Hormetic Response Of Soil Alkaline Phosphatase And The Potential Enzyme Kinetic Mechanism, Diwu Fan, Yujing Jing, Yongli Zhu, Sajjad Ahmad, Jiangang Han

Civil and Environmental Engineering and Construction Faculty Research

Hormesis of soil enzyme that involved in heavy metal has been attracting much more attention for risk assessment of heavy metal toxicity, but insufficient studies were conducted to define the hormetic responses induced by toluene or other organic pollutions. The objectives of this study were to investigate the hormetic responses of soil enzyme induced by toluene and explore the potential enzyme kinetic mechanism. Soil alkaline phosphatase (ALP) activity was regarded as the endpoint to explore the hormetic responses under different doses of toluene (0.0, 0.1, 0.5, 1.0, 2.0, 3.0, 5.0, 10.0, 50.0 and 100.0 μL g−1). Subsequently, we conducted the …

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Self-Stabilizing Token Distribution On Trees With Constant Space, Yuichi Sudo, Ajoy K. Datta, Lawrence L. Larmore, Toshimitsu Masuzawa Aug 2020

Self-Stabilizing Token Distribution On Trees With Constant Space, Yuichi Sudo, Ajoy K. Datta, Lawrence L. Larmore, Toshimitsu Masuzawa

Computer Science Faculty Research

Self-stabilizing and silent distributed algorithms for token distribution in rooted tree networks are given. Initially, each process of a graph holds at most l tokens. Our goal is to distribute the tokens uniformly in the whole network so that every process holds exactly k tokens. In the initial configuration, the total number of tokens in the network may not be nk where n is the number of processes in the network. The root process is given the ability to create a new token or remove a token from the network. We aim to minimize the convergence time, the number of …

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Late Quaternary Climate Variability And Change From Aotearoa New Zealand Speleothems: Progress In Age Modelling, Oxygen Isotope Master Record Construction And Proxy-Model Comparisons, Andrew M. Lorrey, Paul W. Williams, John-Mark Woolley, Nicolas C. Faushereau, Adam Hartland, Helen Bostock, Shaun Eaves, Matthew S. Lachniet, James A. Renwick, Vidya Varma Aug 2020

Late Quaternary Climate Variability And Change From Aotearoa New Zealand Speleothems: Progress In Age Modelling, Oxygen Isotope Master Record Construction And Proxy-Model Comparisons, Andrew M. Lorrey, Paul W. Williams, John-Mark Woolley, Nicolas C. Faushereau, Adam Hartland, Helen Bostock, Shaun Eaves, Matthew S. Lachniet, James A. Renwick, Vidya Varma

Geoscience Faculty Research

We re-evaluated speleothem isotope series from Aotearoa New Zealand that were recently contributed to the Speleothem Isotopes Synthesis and AnaLysis (SISAL) database. COnstructing Proxy Records from Age Models (COPRA) software was used to produce Bayesian age models for those speleothems. The new age modelling helped us examine Late Quaternary temporal coverage for the national speleothem network, and also supported our exploration of three different isotope master record generation techniques using Holocene δ18O data from Waitomo. We then applied the output from one of the isotope master record techniques to test an application case of how climate transfer functions can be …

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Flow Topology In The Confluence Of An Open Channel With Lateral Drainage Pipe, Mohammad Nazari-Sharabian, Moses Karakouzian, Donald Hayes Aug 2020

Flow Topology In The Confluence Of An Open Channel With Lateral Drainage Pipe, Mohammad Nazari-Sharabian, Moses Karakouzian, Donald Hayes

Geoscience Faculty Research

The purpose of this paper is to develop design guidelines for flood control channel height in the vicinity of the confluence of a submerged drainage pipe and a flood control channel. The water exchange in the confluence of an open channel with a lateral drainage pipe produces unique hydraulic characteristics, ultimately affecting the water surface elevation in the channel. An accurate prediction of the water surface elevation is essential in the successful design of a high-velocity channel. By performing several experiments, and utilizing a numerical model (FLOW-3D), this study investigated the impact of submerged lateral drainage pipe discharges into rectangular …

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Snackjack: A Toy Model Of Blackjack, Stewart N. Ethier, Jiyeon Lee Aug 2020

Snackjack: A Toy Model Of Blackjack, Stewart N. Ethier, Jiyeon Lee

UNLV Gaming Research & Review Journal

Snackjack is a highly simplified version of blackjack that was proposed by Ethier (2010) and given its name by Epstein (2013). The eight-card deck comprises two aces, two deuces, and four treys, with aces having value either 1 or 4, and deuces and treys having values 2 and 3, respectively. The target total is 7 (vs. 21 in blackjack), and ace-trey is a natural. The dealer stands on 6 and 7, including soft totals, and otherwise hits. The player can stand, hit, double, or split, but split pairs receive only one card per paircard (like split aces in blackjack), and …

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Interplay Of Trna-Derived Fragments And T Cell Activation In Breast Cancer Patient Survival, Nayang Shan, Ningshan Li, Qile Dai, Lin Hou, Xiting Yan, Amei Amei, Lingeng Lu, Zuoheng Wang Aug 2020

Interplay Of Trna-Derived Fragments And T Cell Activation In Breast Cancer Patient Survival, Nayang Shan, Ningshan Li, Qile Dai, Lin Hou, Xiting Yan, Amei Amei, Lingeng Lu, Zuoheng Wang

Mathematical Sciences Faculty Research

Effector CD8+ T cell activation and its cytotoxic function are positively correlated with improved survival in breast cancer. tRNA-derived fragments (tRFs) have recently been found to be involved in gene regulation in cancer progression. However, it is unclear how interactions between expression of tRFs and T cell activation affect breast cancer patient survival. We used Kaplan–Meier survival and multivariate Cox regression models to evaluate the effect of interactions between expression of tRFs and T cell activation on survival in 1081 breast cancer patients. Spearman correlation analysis and weighted gene co-expression network analysis were conducted to identify genes and pathways that …

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