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Articles 148351 - 148380 of 294572

Full-Text Articles in Physical Sciences and Mathematics

The Motion Of Two Identical Masses Connected By An Ideal String Symmetrically Placed Over A Corner, Asim Gangopadhyaya, Constantin Rasinariu Oct 2016

The Motion Of Two Identical Masses Connected By An Ideal String Symmetrically Placed Over A Corner, Asim Gangopadhyaya, Constantin Rasinariu

Physics: Faculty Publications and Other Works

We introduce a novel, two-mass system that slides up an inclined plane while its center of mass moves down. The system consists of two identical masses connected by an ideal string symmetrically placed over a corner-shaped support. This system is similar to a double-cone that rolls up an inclined set of V-shaped rails. We find the double-cone's motion easy to demonstrate but difficult to analyze. Our example here is more straightforward to follow, and the experimental observations are in good agreement with the theoretical predictions.


Rediscovering Physical Collections Through The Digital Archive: The Jesuit Libraries Provenance Project, Kyle Roberts Oct 2016

Rediscovering Physical Collections Through The Digital Archive: The Jesuit Libraries Provenance Project, Kyle Roberts

History: Faculty Publications and Other Works

Historic library collections offer a rich and underexplored resource for teaching undergraduate and graduate students about new digital approaches, methodologies, and platforms. Their scope and scale can make them difficult to analyze in their physical form, but remediated onto a digital platform, they offer valuable insights into the process of archive creation and the importance of making their content available to audiences that cannot normally access it. The Jesuit Libraries Provenance Project (JLPP) was launched by students, faculty, and library professionals in 2014 to create an online archive of marks of ownership—bookplates, stamps, inscriptions—contained within books from the original library …


The Bright End Of The Z~9 And Z~10 Uv Luminosity Functions Using All Five Candels Fields., R. J. Bouwens, P. A. Oesch, I. Labbe, G. D. Illingworth, G. G. Fazio, D. Coe, Benne W. Holwerda, R. Smit, M. Stefanon, P. G. Van Dokkum, M. Trenti, M. L. N. Ashby, J. S. Huang, L. Spitler, C. Straatman, L. Bradley, D. Magee Oct 2016

The Bright End Of The Z~9 And Z~10 Uv Luminosity Functions Using All Five Candels Fields., R. J. Bouwens, P. A. Oesch, I. Labbe, G. D. Illingworth, G. G. Fazio, D. Coe, Benne W. Holwerda, R. Smit, M. Stefanon, P. G. Van Dokkum, M. Trenti, M. L. N. Ashby, J. S. Huang, L. Spitler, C. Straatman, L. Bradley, D. Magee

Faculty and Staff Scholarship

The deep, wide-area (∼800–900 arcmin2 ) near-infrared/WFC3/IR + Spitzer/IRAC observations over the CANDELS fields have been a remarkable resource for constraining the bright end of high-redshift UV luminosity functions. However, the lack of Hubble Space Telescope (HST) 1.05 μm observations over the CANDELS fields has made it difficult to identify z ∼ 9–10 sources robustly, since such data are needed to confirm the presence of an abrupt Lyman break at 1.2 μm. Here, we report on the successful identification of many such z ∼ 9–10 sources from a new HST program (z9-CANDELS) that targets the highest-probability z ∼ 9–10 galaxy …


Evolution Of Cosmic Filaments And Of Their Galaxy Population From Mhd Cosmological Simulations., C. Gheller, F. Vazza, M. Bruggen, M. Alpaslan, Benne W. Holwerda, A. M. Hopkins, J. Liske Oct 2016

Evolution Of Cosmic Filaments And Of Their Galaxy Population From Mhd Cosmological Simulations., C. Gheller, F. Vazza, M. Bruggen, M. Alpaslan, Benne W. Holwerda, A. M. Hopkins, J. Liske

Faculty and Staff Scholarship

Despite containing about a half of the total matter in the Universe, at most wavelengths the filamentary structure of the cosmic web is difficult to observe. In this work, we use large unigrid cosmological simulations to investigate how the geometrical, thermodynamical and magnetic properties of cosmological filaments vary with mass and redshift (z ≤ 1). We find that the average temperature, length, volume and magnetic field of filaments scales well with their total mass. This reflects the role of self-gravity in shaping their properties and enables statistical predictions of their observational properties based on their mass. We also focus on …


Galaxy And Mass Assembly (Gama) : M–Re Relations Of Z = 0 Bulges, Discs And Spheroids., Rebecca Lange, Amanda J. Moffett, Simon P. Driver, Aaron S. G. Robotham, Claudia Del P. Lagos, Lee S. Kelvin, Christopher Conselice, Berta Margalef-Bentabol, Mehmet Alpaslan, Ivan K. Baldry, Joss Bland-Hawthorn, Malcolm Bremer, Sarah Brough, Michelle Cluver, Matthew Colless, Luke J. M. Davies, Boris Haußler, Benne W. Holwerda, Andrew M. Hopkins, Prajwal R. Kafle, Rebecca Kennedy, Jochen Liske, Steven Phillipps, Cristina C. Popescu, Edward N. Taylor, Richard Tuffs, Eelco Van Kampen, Angus H. Wright Oct 2016

Galaxy And Mass Assembly (Gama) : M–Re Relations Of Z = 0 Bulges, Discs And Spheroids., Rebecca Lange, Amanda J. Moffett, Simon P. Driver, Aaron S. G. Robotham, Claudia Del P. Lagos, Lee S. Kelvin, Christopher Conselice, Berta Margalef-Bentabol, Mehmet Alpaslan, Ivan K. Baldry, Joss Bland-Hawthorn, Malcolm Bremer, Sarah Brough, Michelle Cluver, Matthew Colless, Luke J. M. Davies, Boris Haußler, Benne W. Holwerda, Andrew M. Hopkins, Prajwal R. Kafle, Rebecca Kennedy, Jochen Liske, Steven Phillipps, Cristina C. Popescu, Edward N. Taylor, Richard Tuffs, Eelco Van Kampen, Angus H. Wright

Faculty and Staff Scholarship

We perform automated bulge + disc decomposition on a sample of ∼7500 galaxies from the Galaxy And Mass Assembly (GAMA) survey in the redshift range of 0.002 < z < 0.06 using Structural Investigation of Galaxies via Model Analysis, a wrapper around GALFIT3. To achieve robust profile measurements, we use a novel approach of repeatedly fitting the galaxies, varying the input parameters to sample a large fraction of the input parameter space. Using this method, we reduce the catastrophic failure rate significantly and verify the confidence in the fit independently of χ2. Additionally, using the median of the final fitting values and the 16th and 84th percentile produces more realistic error estimates than those provided by GALFIT, which are known to be underestimated. We use the results of our decompositions to analyse the stellar mass – half-light radius relations of bulges, discs and spheroids. We further investigate the association of components with a parent disc or elliptical relation to provide definite z = 0 disc and spheroid M–Re relations. We conclude by comparing our local disc and spheroid M–Re to simulated data from EAGLE and high-redshift data from Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey-Ultra Deep Survey. We show the potential of using the M–Re relation to study galaxy evolution in both cases but caution that for a fair comparison, all data sets need to be processed and analysed in the same manner.


Variations In Geochemistry And Mineralogy Of Aeolian Dust Deposition To Mountains In Utah And Nevada, Usa, Dylan Binder Dastrup Oct 2016

Variations In Geochemistry And Mineralogy Of Aeolian Dust Deposition To Mountains In Utah And Nevada, Usa, Dylan Binder Dastrup

Theses and Dissertations

Major and trace metal loading to mountains in the western US depends on dust sources, intensity of storms and their availability for transport during snowmelt and runoff. Previous work has been conducted on dust production, composition, and its affect on solar radiation and timing of snow melt. This study was conducted to 1) examine temporal and spatial variability in dust chemistry; 2) evaluate form and availability of major and trace elements in dust; and 3) identify potential dust sources affecting mountains in Utah and Nevada. Spring and summertime dust was collected across northern Utah over the course of three years …


Cellulose-Based Material For Remediation Of Oil Spills, Khaled Khalil Jarrah Oct 2016

Cellulose-Based Material For Remediation Of Oil Spills, Khaled Khalil Jarrah

Chemistry Theses

Oil and organic chemical pollution of aquatic and terrestrial environment is a major concern to the Gulf Countries. The goal of this thesis is to use natural fibers for the remediation of oil-contaminated water. Three natural fibers (cotton, loofa and palm leaves) were chemically modified by silylation and esterification reactions to make the fibers lipophilic. Cotton was the most promising and both chemical processes improved its oil-absorption capacity significantly. Successful modification of the cotton with chlorosilanes (methyl trichloro silane, butyl trichlorosilane, dichlorodimethyl silane, trichloro-3,3 ,3-trifluoropropyl silane) and the alkanoyl chlorides (acetyl, propionyl, butyryl, valeroyl, hexanoyl, and perfluorobutyl chlorides) were supported …


Book Review: The International Atlas Of Mars Exploration: From Spirit To Curiosity: V.2: 2004 To 2014, T. D. Oswalt Oct 2016

Book Review: The International Atlas Of Mars Exploration: From Spirit To Curiosity: V.2: 2004 To 2014, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of The International Atlas of Mars Exploration: from Spirit to Curiosity : V.2: 2004 to 2014 by Philip J. Stooke. 444p bibl index, 9781107030930 $145.00, 9781139344470 LC Call Number: 1000


The Wrecks Of Lake Champlain, Gary C. Kessler Oct 2016

The Wrecks Of Lake Champlain, Gary C. Kessler

Publications

Despite the dozens of historically significant wrecks in the lake, only nine are open for diving as part of the Lake Champlain Underwater Historic Preserve. For visitors to the area, five of the wrecks are easily accessible from Burlington, with four being in the immediate vicinity of Burlington Bay. This article will focus on these five wrecks.


The Four Color Theorem: A Possible New Approach, Matthew Brady Oct 2016

The Four Color Theorem: A Possible New Approach, Matthew Brady

All Student Theses and Dissertations

The goal of this thesis is to explore the topic of graph coloring and expand on existing ideas in the field of Graph Theory. These developments will then be used to provide a possible approach in proving the 4 – color theorem that was made famous by Guthrie in the 1800’s.

Since the theorem was presented, many proofs were presented and eventually disregarded for one reason or another. Today, the types of proofs that are considered correct all rely on a computer. The first of this kind was set forth by Appel and Haken in 1977. The driving idea behind …


Quantitative Analysis Of Acetylsalicylic Acid By Q-Nmr (Quantitative-Nuclear Magnetic Resonance Spectroscopy), Charles Flemming Jr. Oct 2016

Quantitative Analysis Of Acetylsalicylic Acid By Q-Nmr (Quantitative-Nuclear Magnetic Resonance Spectroscopy), Charles Flemming Jr.

All Student Theses and Dissertations

Quantitative analysis is an important step during pharmaceutical drug development. Currently, the pharmaceutical industry uses high performance liquid chromatography (HPLC) for quantitative analysis of organic compounds as the preferred technique. The proton nuclear magnetic resonance (NMR) technique has an inherent ability to quantify a given analyte and may be used to quantify organic compounds. Quantitative nuclear magnetic resonance spectroscopy (q-NMR) of acetylsalicylic acid (ASA) was conducted using tert-butyl alcohol (tert-butanol) as the internal standard and deuterated chloroform (CDCl3) as the solvent. Preparations of ASA solutions in low and high concentration ranges, 1.0 mM – 10.1 …


Circulation, Vol. 22, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Mike Dinniman Oct 2016

Circulation, Vol. 22, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Mike Dinniman

CCPO Circulation

Fall 2016 issue of CCPO Circulation featuring article "I have to Do What to the Model? How Did I Get Here, Part ll" by Mike Dinniman.


Hampton Roads Sea Level Rise Preparedness And Resilience Intergovernmental Pilot Project. Phase 2 Report: Recommendations, Accomplishments And Lessons Learned, Emily E. Steinhilber, Maura Boswell, Carol Considine, Larry Mast Oct 2016

Hampton Roads Sea Level Rise Preparedness And Resilience Intergovernmental Pilot Project. Phase 2 Report: Recommendations, Accomplishments And Lessons Learned, Emily E. Steinhilber, Maura Boswell, Carol Considine, Larry Mast

Hampton Roads Intergovernmental Pilot Project: Reports

Executive Summary

After two years, the Hampton Roads Sea level Rise and Resilience Intergovernmental Planning Pilot Project (Intergovernmental Pilot Project or IPP), convened at Old Dominion University, has come to a successful close. Although the conclusion of the project is different than originally imagined by the drafters of the IPP Charter, the process in and of itself brought hundreds of stakeholders together, built lasting and ongoing relationships, and produced many workable recommendations for the region that can be accomplished by a variety of partnerships. The key deliverables include a whole of government mitigation and adaptation planning process and an integrated …


Impact Of Upper-Tropospheric Temperature Anomalies And Vertical Wind Shear On Tropical Cyclone Evolution Using An Idealized Version Of The Operational Gfdl Hurricane Model, Robert E. Tuleya, Morris Bender, Thomas R. Knutson, Joseph R. Sirutis, Biju Thomas, Isaac Ginis Oct 2016

Impact Of Upper-Tropospheric Temperature Anomalies And Vertical Wind Shear On Tropical Cyclone Evolution Using An Idealized Version Of The Operational Gfdl Hurricane Model, Robert E. Tuleya, Morris Bender, Thomas R. Knutson, Joseph R. Sirutis, Biju Thomas, Isaac Ginis

CCPO Publications

The GFDL hurricane modeling system, initiated in the 1970s, has progressed from a research tool to an operational system over four decades. This system is still in use today in research and operations, and its evolution will be briefly described. This study used an idealized version of the 2014 GFDL model to test its sensitivity across a wide range of three environmental factors that are often identified as key factors in tropical cyclone (TC) evolution: SST, atmospheric stability (upper-air thermal anomalies), and vertical wind shear (westerly through easterly). A wide range of minimum central pressure intensities resulted (905-980 hPa). The …


High Temperature Condensate Clouds In Super-Hot Jupiter Atmospheres, H. R. Wakeford, Channon Visscher, Nikole K. Lewis, Avi M. Mandell Oct 2016

High Temperature Condensate Clouds In Super-Hot Jupiter Atmospheres, H. R. Wakeford, Channon Visscher, Nikole K. Lewis, Avi M. Mandell

Faculty Work Comprehensive List

Deciphering the role of clouds is central to our understanding of exoplanet atmo- spheres, as they have a direct impact on the temperature and pressure structure, and observational properties of the planet. Super-hot Jupiters occupy a temperature regime similar to low mass M-dwarfs, where minimal cloud condensation is expected. However, observations of exoplanets such as WASP-12b (Teq∼2500 K) result in a transmission spectrum indicative of a cloudy atmosphere. We re-examine the temperature and pressure space occupied by these super-hot Jupiter atmospheres, to explore the role of the initial Al- and Ti-bearing condensates as the main source of cloud material. Due …


Simulation And Optimization Of Ant Colony Optimization Algorithm For The Stochiastic Uncapacitated Location-Allocation Problem, Jean-Paul Arnaout, Georges Arnaout, John El Khoury Oct 2016

Simulation And Optimization Of Ant Colony Optimization Algorithm For The Stochiastic Uncapacitated Location-Allocation Problem, Jean-Paul Arnaout, Georges Arnaout, John El Khoury

Engineering Management & Systems Engineering Faculty Publications

This study proposes a novel methodology towards using ant colony optimization (ACO) with stochastic demand. In particular, an optimizationsimulation-optimization approach is used to solve the Stochastic uncapacitated location-allocation problem with an unknown number of facilities, and an objective of minimizing the fixed and transportation costs. ACO is modeled using discrete event simulation to capture the randomness of customers’ demand, and its objective is to optimize the costs. On the other hand, the simulated ACO’s parameters are also optimized to guarantee superior solutions. This approach’s performance is evaluated by comparing its solutions to the ones obtained using deterministic data. The results …


Echocardiography Audit On Patients With Hereditary Haemochromatosis, Lorna Doran Oct 2016

Echocardiography Audit On Patients With Hereditary Haemochromatosis, Lorna Doran

Masters

Background: The European Association for the Study of the Liver (EASL) Guidelines for Hereditary Haemochromatosis (HH) refer specifically to symptomatic Homozygous C282Y patients and provide an algorithm for treating such patients who are predisposed to iron overloading. The British Society of Echocardiography does not make provisions for HH patients per se. Cardiac failure is a known complication of severe iron overload although it is atypical. Aim: To retrospectively investigate if an echocardiogram (echo) was warranted in the HH population at Louth County Hospital (LCH) Venesection Clinic based on the current guidelines. Methods: A cohort of 833 HH patients was reviewed …


The Cosm Newsletter, Georgia Southern University Oct 2016

The Cosm Newsletter, Georgia Southern University

College of Science & Mathematics: News & Publications (2012-2022)

  • Eagles in Training for STEM Careers
  • The Department of Biology Welcomes New Faculty
  • Biology Alumni Move Onward and Upward
  • Georgia Southern's Elite 8 for REU-2016
  • Geologists Investigate Salt Water Intrusion on a Georgia Barrier Island
  • The Georgia Southern Sea Turtle Program at St. Catherines Island: The 2016 Sea Turtle Nesting Season
  • Hatchlings
  • The Department of Mathematical Sciences Welcomes New Faculty
  • Eagles Win Third MacArthur Award
  • Faculty member awarded new Patent on “Engineered lumenized vascular networks and support matrix”
  • The Photonic Nanotechnology Computational Group
  • Edwards participates in NSF "Ideas Lab" to Measure "Big G"
  • Faculty Member Participates in Scholarly Activities
  • Professors …


Data Analytics For Fault Localization In Complex Networks, Maggie X. Cheng, Wei Biao Wu Oct 2016

Data Analytics For Fault Localization In Complex Networks, Maggie X. Cheng, Wei Biao Wu

Computer Science Faculty Research & Creative Works

We consider the problem of identifying the source of failure in a network after receiving alarms or having observed symptoms. To locate the root cause accurately and timely in a large communication system is challenging because a single fault can often result in a large number of alarms, and multiple faults can occur concurrently. In this paper, we present a new fault localization method using a machine-learning approach. We propose to use logistic regression to study the correlation among network events based on end-to-end measurements. Then based on the regression model, we develop fault hypothesis that best explains the observed …


Distributed Fiber-Optic Temperature Sensor Validations Using Field Deployments In The Flooded Orphan Boy Mine Shaft In Butte, Mt, Elliott Mazur Oct 2016

Distributed Fiber-Optic Temperature Sensor Validations Using Field Deployments In The Flooded Orphan Boy Mine Shaft In Butte, Mt, Elliott Mazur

Graduate Theses & Non-Theses

The process of sensor validation through experimentation with the Omnisens Distributed Temperature and Strain (DITEST) Brillouin Optical Time Domain Analyzer (BOTDA) proved to be a challenging project. The project encompassed sensor calibrations, system error minimization, sensor network design and deployment, and the characterization of temperatures in the Orphan Boy Mine shaft. Fiber-optic cable sensor calibrations yielded linear relationship coefficients 0.6-1.0MHZ/°F, indicating a strong positive correlation between Brillouin Frequency Shifts and temperature. Calibrated sensors demonstrated accuracies near ±0.8°F using the corrected error bounds from residual analyses as the benchmark. Fiber-optic measurement accuracy and repeatability were controlled by user-selected signal interrogator settings …


A Generalized Class Of Exponentiated Modified Weibull Distribution With Applications, Shusen Pu, Broderick O. Oluyede, Yuqi Qui, Daniel F. Linder Oct 2016

A Generalized Class Of Exponentiated Modified Weibull Distribution With Applications, Shusen Pu, Broderick O. Oluyede, Yuqi Qui, Daniel F. Linder

Mathematical Sciences: Faculty Publications

In this paper, a new class of five parameter gamma-exponentiated or generalized modified Weibull (GEMW) distribution which includes exponential, Rayleigh, Weibull, modified Weibull, exponentiated Weibull, exponentiated exponential, exponentiated modified Weibull, exponentiated modified exponential, gamma-exponentiated exponential, gamma-exponentiated Rayleigh, gamma-modified Weibull, gamma-modified exponential, gamma-Weibull, gamma-Rayleigh and gamma-exponential distributions as special cases is proposed and studied. Mathematical properties of this new class of distributions including moments, mean deviations, Bonferroni and Lorenz curves, distribution of order statistics and Renyi entropy are presented. Maximum likelihood estimation technique is used to estimate the model parameters and applications to real data sets presented in order to illustrate …


Binary Black Hole Mergers In The First Advanced Ligo Observing Run, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Oct 2016

Binary Black Hole Mergers In The First Advanced Ligo Observing Run, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The first observational run of the Advanced LIGO detectors, from September 12, 2015 to January 19, 2016, saw the first detections of gravitational waves from binary black hole mergers. In this paper, we present full results from a search for binary black hole merger signals with total masses up to 100M⊙ and detailed implications from our observations of these systems. Our search, based on general-relativistic models of gravitational-wave signals from binary black hole systems, unambiguously identified two signals, GW150914 and GW151226, with a significance of greater than 5σ over the observing period. It also identified a third possible signal, …


Improved Analysis Of Gw150914 Using A Fully Spin-Precessing Waveform Model, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Oct 2016

Improved Analysis Of Gw150914 Using A Fully Spin-Precessing Waveform Model, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

This paper presents updated estimates of source parameters for GW150914, a binary black-hole coalescence event detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 [Abbott et al. Phys. Rev. Lett. 116, 061102 (2016).]. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] presented parameter estimation of the source using a 13-dimensional, phenomenological precessing-spin model (precessing IMRPhenom) and an 11-dimensional nonprecessing effective-one body (EOB) model calibrated to numerical-relativity simulations, which forces spin alignment (nonprecessing EOBNR). Here, we present new results that include a 15-dimensional precessing-spin waveform model (precessing EOBNR) developed within the EOB formalism. We find good agreement …


Computational Fluid Dynamics Study Of Molten Steel Flow Patterns And Particle-Wall Interactions Inside A Slide-Gate Nozzle By A Hybrid Turbulent Model, Mahdi Mohammadi-Ghaleni, Mohsen Asle Zaeem, Jeffrey D. Smith, Ronald J. O'Malley Oct 2016

Computational Fluid Dynamics Study Of Molten Steel Flow Patterns And Particle-Wall Interactions Inside A Slide-Gate Nozzle By A Hybrid Turbulent Model, Mahdi Mohammadi-Ghaleni, Mohsen Asle Zaeem, Jeffrey D. Smith, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Melt flow patterns and turbulence inside a slide-gate throttled submerged entry nozzle (SEN) were studied using Detached–Eddy Simulation (DES) model, which is a combination of Reynolds–Averaged Navier–Stokes (RANS) and Large–Eddy Simulation (LES) models. The DES switching criterion between RANS and LES was investigated to closely reproduce the flow structures of low and high turbulence regions similar to RANS and LES simulations, respectively. The melt flow patterns inside the nozzle were determined by k–ε (a RANS model), LES, and DES turbulent models, and convergence studies were performed to ensure reliability of the results. Results showed that the DES model has significant …


Quantum Critical Behavior Of The Superfluid-Mott Glass Transition, Thomas Vojta, Jack Crewse, Martin Puschmann, Daniel Arovas, Yury Kiselev Oct 2016

Quantum Critical Behavior Of The Superfluid-Mott Glass Transition, Thomas Vojta, Jack Crewse, Martin Puschmann, Daniel Arovas, Yury Kiselev

Physics Faculty Research & Creative Works

We investigate the zero-temperature superfluid to insulator transitions in a diluted two-dimensional quantum rotor model with particle-hole symmetry. We map the Hamiltonian onto a classical (2+1)-dimensional XY model with columnar disorder which we analyze by means of large-scale Monte Carlo simulations. For dilutions below the lattice percolation threshold, the system undergoes a generic superfluid-Mott glass transition. In contrast to other quantum phase transitions in disordered systems, its critical behavior is of conventional power-law type with universal (dilution-independent) critical exponents z=1.52(3), ν =1.16(5), ß/ν =0.48(2), γ/ν=2.52(4), and η = -0.52(4). These values agree with and improve upon earlier Monte Carlo results …


Hitting The Goalpost: Calculating The Fine Line Between Winning And Losing A Penalty Shootout, Ralf Widenhorn Oct 2016

Hitting The Goalpost: Calculating The Fine Line Between Winning And Losing A Penalty Shootout, Ralf Widenhorn

Physics Faculty Publications and Presentations

The Portland Timbers won their first Major League Soccer (MLS) Cup Championship in December 2015. However, if it had not been for a kind double goalpost miss during a penalty shootout a few weeks earlier, the Timbers would never have been in the finals. On Oct. 30th, after what has been called "the greatest penalty kick shootout in MLS history," featuring a combined 22 penalties that included penalties by both goalkeepers, the Timbers won their first-round playoff against Sporting Kansas City. During the thrilling shootout, which can be watched on the MLS website, Sporting had two potentially game-winning penalties miss …


A Dual-Porosity-Stokes Model And Finite Element Method For Coupling Dual-Porosity Flow And Free Flow, Jiangyong Hou, Meilan Qiu, Xiaoming He, Chaohua Guo, Mingzhen Wei, Baojun Bai Oct 2016

A Dual-Porosity-Stokes Model And Finite Element Method For Coupling Dual-Porosity Flow And Free Flow, Jiangyong Hou, Meilan Qiu, Xiaoming He, Chaohua Guo, Mingzhen Wei, Baojun Bai

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we propose and numerically solve a new model considering confined flow in dual-porosity media coupled with free flow in embedded macrofractures and conduits. Such situation arises, for example, for fluid flows in hydraulic fractured tight/shale oil/gas reservoirs. The flow in dual-porosity media, which consists of both matrix and microfractures, is described by a dual-porosity model. And the flow in the macrofractures and conduits is governed by the Stokes equation. Then the two models are coupled through four physically valid interface conditions on the interface between dual-porosity media and macrofractures/conduits, which play a key role in a physically …


Sn Vacancies In Photorefractive Sn2P2S6 Crystals: An Electron Paramagnetic Resonance Study Of An Optically Active Hole Trap, Eric M. Golden, Sergey A. Basun, D. R. Evans, A. A. Grabar, I. M. Stoika, Nancy C. Giles, Larry E. Halliburton Oct 2016

Sn Vacancies In Photorefractive Sn2P2S6 Crystals: An Electron Paramagnetic Resonance Study Of An Optically Active Hole Trap, Eric M. Golden, Sergey A. Basun, D. R. Evans, A. A. Grabar, I. M. Stoika, Nancy C. Giles, Larry E. Halliburton

Faculty Publications

Electron paramagnetic resonance (EPR) is used to identify the singly ionized charge state of the Sn vacancy (V−Sn) in single crystals of Sn2P2S6 (often referred to as SPS). These vacancies, acting as a hole trap, are expected to be important participants in the photorefractive effect observed in undoped SPS crystals. In as-grown crystals, the Sn vacancies are doubly ionized (V2−Sn) with no unpaired spins. They are then converted to a stable EPR-active state when an electron is removed (i.e., a hole is trapped) during an illumination below 100 K …


Physical Science Day: Design, Implementation, And Assessment, Liang Zeng, Mark A. Cunningham, Steven C. Tidrow, K. Christopher Smith, Jerry Contreras Oct 2016

Physical Science Day: Design, Implementation, And Assessment, Liang Zeng, Mark A. Cunningham, Steven C. Tidrow, K. Christopher Smith, Jerry Contreras

Physics & Astronomy Faculty Publications

Physical Science Day at The University of Texas–Pan American (UTPA), in collaboration with the Edinburg Consolidated Independent School District, has been designed, developed and implemented to address an identified fundamental shortcoming in our educational process within this primarily (90+%) Hispanic serving border region. Physical Science Day overcomes the lack of knowledge about what physics is by raising youth awareness of physics as the foundation of science, engineering and technology disciplines, through activities including hands-on laboratory experiments, career orientation, and higher educational student and graduated student testimonials. Thus, Physical Science Day encourages, attracts, and enables more Hispanic youth towards science, technology …


99mtc-Hexamethylpropyleneamine Oxime Imaging For Early Detection Of Acute Lung Injury In Rats Exposed To Hyperoxia Or Lipopolysaccharide Treatment, Said H. Audi, Anne V. Clough, Steven T. Haworth, Meetha Medhora, Mahsa Ranji, John C. Densmore, Elizabeth R. Jacobs Oct 2016

99mtc-Hexamethylpropyleneamine Oxime Imaging For Early Detection Of Acute Lung Injury In Rats Exposed To Hyperoxia Or Lipopolysaccharide Treatment, Said H. Audi, Anne V. Clough, Steven T. Haworth, Meetha Medhora, Mahsa Ranji, John C. Densmore, Elizabeth R. Jacobs

Biomedical Engineering Faculty Research and Publications

99mTc-Hexamethylpropyleneamine oxime (HMPAO) is a clinical single-photon emission computed tomography biomarker of tissue oxidoreductive state. Our objective was to investigate whether HMPAO lung uptake can serve as a preclinical marker of lung injury in two well-established rat models of human acute lung injury (ALI).

Rats were exposed to >95% O2 (hyperoxia) or treated with intratracheal lipopolysaccharide (LPS), with first endpoints obtained 24 h later. HMPAO was administered intravenously before and after treatment with the glutathione-depleting agent diethyl maleate (DEM), scintigraphy images were acquired, and HMPAO lung uptake was quantified from the images. We also measured breathing rates, heart …