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Articles 451 - 480 of 1382

Full-Text Articles in Physical Sciences and Mathematics

Ionospheric Gravity Waves Driven By Oceanic Gravity Waves In Resonance: A Modeling Study In Search Of Their Spectra, Michael P. Hickey, Yonghui Yu Sep 2017

Ionospheric Gravity Waves Driven By Oceanic Gravity Waves In Resonance: A Modeling Study In Search Of Their Spectra, Michael P. Hickey, Yonghui Yu

Publications

Ionospheric observations associated with the 2011 Tohoku tsunami have revealed gravity waves having spectral characteristics that depend on their proximity to the epicenter. There is a preponderance of medium-scale waves in the vicinity of the epicenter, a significant bifurcation into short- and long-period waves over the Hawaiian archipelago, and a narrow and rich spectrum of waves over the West Coast and inland of the United States (U.S.). Guided by these previous observations, we consider wave sources as triads of nonlinearly interacting oceanic gravity waves, whose wave parameters satisfy resonant conditions. These waves are simulated using a 2-D nonlinear model describing …

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Characteristics Of Mesospheric Gravity Waves Over Antarctica Observed By Angwin (Antarctic Gravity Wave Instrument Network) Imagers Using 3-D Spectral Analyses, Takashi S. Matsuda, Takuji Nakamura, Mitsumu K. Ejiri, Masaki Tsutsumi, Yoshihiro Tomikawa, Michael J. Taylor, Yucheng Zhao, Pierre-Dominique Pautet, Damian J. Murphy, Tracy Moffat-Griffin Sep 2017

Characteristics Of Mesospheric Gravity Waves Over Antarctica Observed By Angwin (Antarctic Gravity Wave Instrument Network) Imagers Using 3-D Spectral Analyses, Takashi S. Matsuda, Takuji Nakamura, Mitsumu K. Ejiri, Masaki Tsutsumi, Yoshihiro Tomikawa, Michael J. Taylor, Yucheng Zhao, Pierre-Dominique Pautet, Damian J. Murphy, Tracy Moffat-Griffin

Publications

We have obtained horizontal phase velocity distributions of the gravity waves around 90 km from four Antarctic airglow imagers, which belong to an international airglow imager/instrument network known as ANGWIN (Antarctic Gravity Wave Instrument Network). Results from the airglow imagers at Syowa (69°S, 40°E), Halley (76°S, 27°W), Davis (69°S, 78°E), and McMurdo (78°S, 167°E) were compared, using a new statistical analysis method based on 3-D Fourier transform (Matsuda et al., 2014) for the observation period between 7 April and 21 May 2013. Significant day-to-day and site-to-site differences were found. The averaged phase velocity spectrum during the observation period showed preferential …

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Laplacian Distribution And Domination, Domingos M. Cardoso, David P. Jacobs, Vilmar Trevisan Sep 2017

Laplacian Distribution And Domination, Domingos M. Cardoso, David P. Jacobs, Vilmar Trevisan

Publications

No abstract provided.

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Mobile Radar As An Undergraduate Education And Research Tool: The Erau C-Breese Field Experience With The Doppler On Wheels, Shawn M. Milrad, Christopher G. Herbster Sep 2017

Mobile Radar As An Undergraduate Education And Research Tool: The Erau C-Breese Field Experience With The Doppler On Wheels, Shawn M. Milrad, Christopher G. Herbster

Publications

Embry-Riddle Aeronautical University Convective-Boundary Research Engaging Educational Student Experiences (ERAU C-BREESE) was an 18-day National Science Foundation (NSF)-funded educational Doppler on Wheels (DOW) deployment through the Center for Severe Weather Research in May 2015. ERAU C-BREESE had three primary areas of focus: meteorological field observations and research, undergraduate experiential learning, and local community outreach. ERAU undergraduate meteorology students had the unique opportunity to forecast for, collect, and analyze field measurements of sea-breeze processes and convection. The scientific objectives of ERAU C-BREESE were to forecast, observe, and analyze central Florida sea-breeze processes and thunderstorms by combining a DOW with more traditional …

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Evaluating Student Perceptions And Learning Outcomes: Differences Between Sla-Able And Non-Sla-Able Introductory Programming Courses, Christina M. Frederick, Matthew B. Pierce, Andrew Griggs, Lulu Sun Sep 2017

Evaluating Student Perceptions And Learning Outcomes: Differences Between Sla-Able And Non-Sla-Able Introductory Programming Courses, Christina M. Frederick, Matthew B. Pierce, Andrew Griggs, Lulu Sun

Publications

Engineering, computer science and subsequently knowledge of programming language is an increasingly vital skill in today’s workforce. First year engineering students are introduced to programming in addition to rigorous course loads in their first year. Second Language Acquisition (SLA) has been applied to programming course content delivery and has shown promise as an effective means of better educating new students. Results will be presented from a NSF funded study conducted over the past two years. SLA was applied to an introductory engineering course that teaches basic programming skills in a Blended learning environment (SLA-aBLe). This study examined four semesters worth …

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Influence Of Velocity Fluctuations On The Kelvin-Helmholtz Instability And Its Associated Mass Transport, Katariina Nykyri, Xuanye Ma, Andrew Dimmock, Claire Foullon, Antonius Otto, Adnane Osmane Sep 2017

Influence Of Velocity Fluctuations On The Kelvin-Helmholtz Instability And Its Associated Mass Transport, Katariina Nykyri, Xuanye Ma, Andrew Dimmock, Claire Foullon, Antonius Otto, Adnane Osmane

Publications

Kelvin-Helmholtz instability (KHI) and associated magnetic reconnection and diffusion processes provide plasma transport from solar wind into the magnetosphere. The efficiency of this transport depends on the magnetosheath and magnetospheric plasma and field properties at the vicinity of the magnetopause. Our recent statistical study using data from the Time History of Events and Macroscale Interactions during Substorms spacecraft indicates that the amplitude of the magnetosheath velocity fluctuations perpendicular to the magnetopause can be substantial. We have performed a series of local macroscale 2.5-dimensional magnetohydrodynamic simulations of the KHI during strongly northward interplanetary magnetic field and with the initial plasma parameters …

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A Regression Model To Predict Stock Market Mega Movements And/Or Volatility Using Both Macroeconomic Indicators & Fed Bank Variables, Timothy A. Smith, Alcuin Rajan Sep 2017

A Regression Model To Predict Stock Market Mega Movements And/Or Volatility Using Both Macroeconomic Indicators & Fed Bank Variables, Timothy A. Smith, Alcuin Rajan

Publications

In finance, regression models or time series moving averages can be used to determine the value of an asset based on its underlying traits. In prior work we built a regression model to predict the value of the S&P 500 based on macroeconomic indicators such as gross domestic product, money supply, produce price and consumer price indices. In this present work this model is updated both with more data and an adjustment in the input variables to improve the coefficient of determination. A scheme is also laid out to alternately define volatility rather than using common tools such as the …

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Secondary Gravity Wave Generation Over New Zealand During The Deepwave Campaign, Katrina Bossert, Christopher G. Kruse, Christopher J. Heale, David C. Fritts, Bifford P. Williams, Jonathan B. Snively, Pierre-Dominique Pautet, Michael J. Taylor Aug 2017

Secondary Gravity Wave Generation Over New Zealand During The Deepwave Campaign, Katrina Bossert, Christopher G. Kruse, Christopher J. Heale, David C. Fritts, Bifford P. Williams, Jonathan B. Snively, Pierre-Dominique Pautet, Michael J. Taylor

Publications

Multiple events during the Deep Propagating Gravity Wave Experiment measurement program revealed mountain wave (MW) breaking at multiple altitudes over the Southern Island of New Zealand. These events were measured during several research flights from the National Science Foundation/National Center for Atmospheric Research Gulfstream V aircraft, utilizing a Rayleigh lidar, an Na lidar, and an Advanced Mesospheric Temperature Mapper simultaneously. A flight on 29 June 2014 observed MWs with horizontal wavelengths of ~80–120 km breaking in the stratosphere from ~10 to 50 km altitude. A flight on 13 July 2014 observed a horizontal wavelength of ~200–240 km MW extending from …

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Detailed Characteristics Of Radiation Belt Electrons Revealed By Csswe/Reptile Measurements: Geomagnetic Activity Response And Precipitation Observation, Kun Zhang, X. Li, Q. Schiller, D. Gerhardt, H. Zhao, R. Millan Aug 2017

Detailed Characteristics Of Radiation Belt Electrons Revealed By Csswe/Reptile Measurements: Geomagnetic Activity Response And Precipitation Observation, Kun Zhang, X. Li, Q. Schiller, D. Gerhardt, H. Zhao, R. Millan

Publications

Earth’s outer radiation belt electrons are highly dynamic. We study the detailed characteristics of relativistic electrons in the outer belt using measurements from the Colorado Student Space Weather Experiment (CSSWE) mission, a low Earth orbit (LEO) CubeSat, which traverses the radiation belt four times in one orbit (~1.5 h) and has the advantage of measuring the dynamic activities of the electrons including their rapid precipitation. We focus on the measured electron response to geomagnetic activity for different energies to show that there are abundant sub-MeV electrons in the inner belt and slot region. These electrons are further enhanced during active …

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Elliptic Solutions And Solitary Waves Of A Higher Order Kdv-Bbm Long Wave Equation, S.C. Mancas, Ronald Adams Aug 2017

Elliptic Solutions And Solitary Waves Of A Higher Order Kdv-Bbm Long Wave Equation, S.C. Mancas, Ronald Adams

Publications

We provide conditions for existence of hyperbolic, unbounded periodic and elliptic solutions in terms of Weierstrass ℘ functions of both third and fifth-order KdV–BBM (Korteweg-de Vries–Benjamin, Bona & Mahony) regularized long wave equation. An analysis for the initial value problem is developed together with a local and global well-posedness theory for the third-order KdV–BBM equation. Traveling wave reduction is used together with zero boundary conditions to yield solitons and periodic unbounded solutions, while for nonzero boundary conditions we find solutions in terms of Weierstrass elliptic ℘ functions. For the fifth-order KdV–BBM equation we show that a parameter γ = 1/12 …

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Stellar Stream Candidates In The Solar Neighborhood Found In The Lamost Dr3 And Tgas, X. L. Liang, Terry Oswalt, J. K. Zhao, Y. Q. Chen, G. Zhao Aug 2017

Stellar Stream Candidates In The Solar Neighborhood Found In The Lamost Dr3 And Tgas, X. L. Liang, Terry Oswalt, J. K. Zhao, Y. Q. Chen, G. Zhao

Publications

We have cross-matched the LAMOST DR3 with the Gaia DR1 TGAS cata- logs and obtained a sample of 166,827 stars with reliable kinematics. A technique based on the wavelet transform was applied to detect significant overdensities in velocity space among five subsamples divided by spatial position. In total, 16 sig- nificant overdensities of stars with very similar kinematics were identified. Among these, four are new stream candidates and the rest are previously known groups. Both the U-V velocity and metallicity distributions of the local sample show a clear gap between the Hercules structure and the Hyades-Pleiades structure. The U-V positions …

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Stellar Stream Candidates In The Solar Neighborhood Found In The Lamost Dr3 And Tgas, X. L. Liang, J. K. Zhao, T. D. Oswalt, Y. Q. Chen, L. Zhang, G. Zhao Aug 2017

Stellar Stream Candidates In The Solar Neighborhood Found In The Lamost Dr3 And Tgas, X. L. Liang, J. K. Zhao, T. D. Oswalt, Y. Q. Chen, L. Zhang, G. Zhao

Publications

We have cross-matched the LAMOST DR3 with the Gaia DR1 TGAS catalogs and obtained a sample of 166,827 stars with reliable kinematics. A technique based on the wavelet transform was applied to detect significant overdensities in velocity space among five subsamples divided by spatial position. In total, 16 significant overdensities of stars with very similar kinematics were identified. Among these, four are new stream candidates and the rest are previously known groups. Both the U–V velocity and metallicity distributions of the local sample show a clear gap between the Hercules structure and the Hyades–Pleiades structure. The U– …

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Magnetospherically-Trapped Dust And A Possible Model For The Unusual Transits At Wd1145+017, J. Farihi, Ted Von Hippel, J. E. Pringle Aug 2017

Magnetospherically-Trapped Dust And A Possible Model For The Unusual Transits At Wd1145+017, J. Farihi, Ted Von Hippel, J. E. Pringle

Publications

The rapidly evolving dust and gas extinction observed towardsWD1145+017 has opened a real-time window onto the mechanisms for destruction-accretion of planetary bodies onto white dwarf stars, and has served to underline the importance of considering the dynamics of dust particles around such objects. Here it is argued that the interaction between (charged) dust grains and the stellar magnetic field is an important ingredient in understanding the physical distribution of infrared emitting particles in the vicinity of such white dwarfs. These ideas are used to suggest a possible model for WD 1145+017 in which the unusual transit shapes are caused by …

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Correlation Of Trichome Density And Length And Polyphenol Fluorescence With Susceptibility Of Five Cucurbits To Didymella Bryoniae, Gabriel Rennberger, A. P. Keinath, M. Hess Aug 2017

Correlation Of Trichome Density And Length And Polyphenol Fluorescence With Susceptibility Of Five Cucurbits To Didymella Bryoniae, Gabriel Rennberger, A. P. Keinath, M. Hess

Publications

The fungal pathogen Didymella bryoniae causes gummy stem blight and black rot on a broad spectrum of cucurbits. However the substantial differences in susceptibility among Cucurbitaceae are not well studied. Susceptibility was characterized with muskmelon (Cucumis melo), watermelon (Citrullus lanatus), cucumber (Cucumis sativus), pumpkin (Cucurbita pepo), and zucchini (C. pepo). Lesion diameters on leaf disks inoculated with agar plugs were measured 7 days after inoculation, and the necrotized areas of leaf disks inoculated with conidial suspensions were measured 48 h after inoculation (hai). For each species, the number of trichomes …

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Variations In Biocorona Formation Related To Defects In The Structure Of Single Walled Carbon Nanotubes And The Hyperlipidemic Disease State, Achyut J. Raghavendra, Kristofer Fritz, Sherleen Fu, Jared M. Brown, Ramakrishna Podila, Jonathan H. Shannahan Aug 2017

Variations In Biocorona Formation Related To Defects In The Structure Of Single Walled Carbon Nanotubes And The Hyperlipidemic Disease State, Achyut J. Raghavendra, Kristofer Fritz, Sherleen Fu, Jared M. Brown, Ramakrishna Podila, Jonathan H. Shannahan

Publications

Ball-milling utilizes mechanical stress to modify properties of carbon nanotubes (CNTs) including size, capping, and functionalization. Ball-milling, however, may introduce structural defects resulting in altered CNT-biomolecule interactions. Nanomaterial-biomolecule interactions result in the formation of the biocorona (BC), which alters nanomaterial properties, function, and biological responses. The formation of the BC is governed by the nanomaterial physicochemical properties and the physiological environment. Underlying disease states such as cardiovascular disease can alter the biological milieu possibly leading to unique BC identities. In this ex vivo study, we evaluated variations in the formation of the BC on single-walled CNTs (SWCNTs) due to physicochemical …

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Forces And Disease: Electrostatic Force Differences Caused By Mutations In Kinesin Motor Domains Can Distinguish Between Disease-Causing And Non-Disease-Causing Mutations, Lin Li, Yunhui Peng, Subash Godar, Ivan Getov, Shaolei Teng, Joshua Alper, Emil Alexov Aug 2017

Forces And Disease: Electrostatic Force Differences Caused By Mutations In Kinesin Motor Domains Can Distinguish Between Disease-Causing And Non-Disease-Causing Mutations, Lin Li, Yunhui Peng, Subash Godar, Ivan Getov, Shaolei Teng, Joshua Alper, Emil Alexov

Publications

The ability to predict if a given mutation is disease-causing or not has enormous potential to impact human health. Typically, these predictions are made by assessing the effects of mutation on macromolecular stability and amino acid conservation. Here we report a novel feature: the electrostatic component of the force acting between a kinesin motor domain and tubulin. We demonstrate that changes in the electrostatic component of the binding force are able to discriminate between disease-causing and non-disease-causing mutations found in human kinesin motor domains using the receiver operating characteristic (ROC). Because diseases may originate from multiple effects not related to …

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Traveling Wave Solutions For Wave Equations With Exponential Nonlinearities, S. C. Mancas, H. C. Rosu, M. Perez-Maldonado Aug 2017

Traveling Wave Solutions For Wave Equations With Exponential Nonlinearities, S. C. Mancas, H. C. Rosu, M. Perez-Maldonado

Publications

We use a simple method which leads to the quadrature involved in obtaining the traveling wave solutions of wave equations with one and two exponential nonlinearities. When the constant term in the integrand is zero, implicit solutions in terms of hypergeometric functions are obtained while when that term is nonzero we give all the basic traveling wave solutions based on a detailed study of the corresponding elliptic equations of several well-known particular cases with important applications in physics.

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A Convenient Miniature Test Platform For Polyelectrolyte Membrane Fuel-Cell Research, Jamie A. Shetzline, Saheed Bukola, Stephen E. Creager Jul 2017

A Convenient Miniature Test Platform For Polyelectrolyte Membrane Fuel-Cell Research, Jamie A. Shetzline, Saheed Bukola, Stephen E. Creager

Publications

A simple and convenient small-scale fuel-cell test platform was created from a commercial compression fitting and graphite rod current collectors and used to conduct diagnostic tests on disk-shaped membrane-electrode assemblies (MEAs) fabricated from Nafion membranes and Nafion-impregnated platinum-on-carbon-cloth anodes and cathodes. A key advantage of this test platform is that it requires very little material, perhaps just a few milligrams, to conduct a fuel-cell test on a supported catalyst. Electrochemically-active surface area (ECSA) values for supported platinum on carbon-cloth electrodes were obtained by in-situ(in the fuel cell) and ex-situ (in liquid electrolyte) cyclic voltammetry on similarly-prepared electrodes, and values …

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A Revision Of Prespelea Park (Staphylinidae, Pselaphinae), Michael S. Caterino, Laura M. Vásquez-Vélez Jul 2017

A Revision Of Prespelea Park (Staphylinidae, Pselaphinae), Michael S. Caterino, Laura M. Vásquez-Vélez

Publications

We revise the genus Prespelea Park, redefining and redescribing the two previously known species, P.copelandi Park and P. quirsfeldi Park, and adding ten new species: P. parki Caterino & Vásquez-Vélez, sp. n., P.minima Caterino & Vásquez-Vélez, sp. n., P. morsei Caterino & Vásquez-Vélez, sp. n., P. divergens Caterino & Vásquez-Vélez, sp. n., P. carltoni Caterino & Vásquez-Vélez, sp. n., P. myersae Caterino & Vásquez-Vélez, sp. n., P. georgiensis Caterino & Vásquez-Vélez, sp. n., P. enigma Caterino & Vásquez-Vélez, sp. n., P. wagneriCaterino & Vásquez-Vélez, sp. n., and P. basalis Caterino …

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Creating An Experimental Learning And Research Driven Spacesuit Lab For Erau, Ryan L. Kobrick, Erik Seedhouse Jul 2017

Creating An Experimental Learning And Research Driven Spacesuit Lab For Erau, Ryan L. Kobrick, Erik Seedhouse

Publications

This paper evaluates key functional data parameters that must be considered for suborbital spaceflight participants wearing pressurized suits for intravehicular activity (IVA). Data parameters of an analog spacesuit worn in an analog flight environment were obtained from 40 civilian participants using the Suborbital Space Flight Simulator (SSFS) at Embry-Riddle Aeronautical University (ERAU) while donning Final Frontier Design’s (FFD) fully pressurized third-generation spacesuit as part of their training for Project PoSSUM (the Polar Suborbital Science in the Upper Mesosphere Project). The physiological data collected included: blood pressure, electrocardiograms, heart rate, grip strength, and skin temperature. These parameters were measured using a …

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Local Time Asymmetry Of Saturn's Magnetosheath Flows, B. Burkholder, P. A. Delamere, X. Ma, M. F. Thomsen, R. J. Wilson, F. Bagenal Jun 2017

Local Time Asymmetry Of Saturn's Magnetosheath Flows, B. Burkholder, P. A. Delamere, X. Ma, M. F. Thomsen, R. J. Wilson, F. Bagenal

Publications

Using gross averages of the azimuthal component of flow in Saturn's magnetosheath, we find that flows in the prenoon sector reach a maximum value of roughly half that of the postnoon side. Corotational magnetodisc plasma creates a much larger flow shear with solar wind plasma prenoon than postnoon. Maxwell stress tensor analysis shows that momentum can be transferred out of the magnetosphere along tangential field lines if a normal component to the boundary is present, i.e., field lines which pierce the magnetopause. A Kelvin‐Helmholtz unstable flow gives rise to precisely this situation, as intermittent reconnection allows the magnetic field to …

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Traveling Wave Solutions To Kawahara And Related Equations, S.C. Mancas Jun 2017

Traveling Wave Solutions To Kawahara And Related Equations, S.C. Mancas

Publications

Traveling wave solutions to Kawahara equation (KE), transmission line (TL), and Korteweg-de Vries (KdV) equation are found by using an elliptic function method which is more general than the tanh-method. The method works by assuming that a polynomial ansatz satisfies a Weierstrass equation, and has two advantages: first, it reduces the number of terms in the ansatz by an order of two, and second, it uses Weierstrass functions which satisfy an elliptic equation for the dependent variable instead of the hyperbolic tangent functions which only satisfy the Riccati equation with constant coefficients. When the polynomial ansatz in the traveling wave …

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First Na Lidar Measurements Of Turbulence Heat Flux, Thermal Diffusivity, And Energy Dissipation Rate In The Mesopause Region, Yafang Guo, Alan Z. Liu, Chester S. Gardner Jun 2017

First Na Lidar Measurements Of Turbulence Heat Flux, Thermal Diffusivity, And Energy Dissipation Rate In The Mesopause Region, Yafang Guo, Alan Z. Liu, Chester S. Gardner

Publications

Turbulence is ubiquitous in the mesopause region, where the atmospheric stability is low and wave breaking is frequent. Measuring turbulence is challenging in this region and is traditionally done by rocket soundings and radars. In this work, we show for the first time that the modern Na wind/temperature lidar located at Andes Lidar Observatory in Cerro Pachón, Chile, is able to directly measure the turbulence perturbations in temperature and vertical wind between 85 and 100 km. Using 150 h of lidar observations, we derived the frequency (ω) and vertical wave number (m) spectra for both gravity …

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Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al. Jun 2017

Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10∶11:58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2 þ8.4 −6.0M⊙ and 19.4 þ5.3 −5.9M⊙ (at the 90% credible level). The black hole spins are best constrained through measurement of the effective inspiral spin parameter, …

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Electromagnetic Radio Frequency Heating In The Pulsed Electric Current Sintering (Pecs) Process, Yufei Liu, D. H. Liebenberg Jun 2017

Electromagnetic Radio Frequency Heating In The Pulsed Electric Current Sintering (Pecs) Process, Yufei Liu, D. H. Liebenberg

Publications

Pulsed electric current sintering offers rapid sintering of many materials compared with hot press sintering. Earlier studies had demonstrated that neither sparks nor plasma formation occur in a typical apparatus such as Dr. Sinter™. Hitchcock et al. showed that electromagnetic radio frequency (rf) emission occurred during the pulsing current and suggested this emission was a relevant augmentation to the hot press sintering in addition to the current flow in the specimen. In this report the importance of rf emission in the sintering process is demonstrated and opportunities to further exploit this approach to improve the sintering process are suggested.

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Book Review: Shoot The Moon: A Complete Guide To Lunar Imaging, T. D. Oswalt Jun 2017

Book Review: Shoot The Moon: A Complete Guide To Lunar Imaging, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Shoot the Moon: a Complete Guide to Lunar Imaging by Dupont-Bloch, Nicolas. Cambridge, 2016, 323 p index, 9781107548442 $39.95, 9781316657867 $32.00.

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Search For Gravitational Waves Associated With Gamma-Ray Bursts During The First Advanced Ligo Observing Run And Implications For The Origin Of Grb 150906b, B. P. Abbott, K. Gill, B. Hughey, J. W. W. Pratt, E. Rhoades, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al. Jun 2017

Search For Gravitational Waves Associated With Gamma-Ray Bursts During The First Advanced Ligo Observing Run And Implications For The Origin Of Grb 150906b, B. P. Abbott, K. Gill, B. Hughey, J. W. W. Pratt, E. Rhoades, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We present the results of the search for gravitational waves (GWs) associated with γ-ray bursts detected during the first observing run of the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO). We find no evidence of a GW signal for any of the 41 γ-ray bursts for which LIGO data are available with sufficient duration. For all γ-ray bursts, we place lower bounds on the distance to the source using the optimistic assumption that GWs with an energy of ${10}^{-2}{M}_{\odot }{c}^{2}$ were emitted within the $16$–$500$ Hz band, and we find a median 90% confidence limit of 71 Mpc at 150 Hz. …

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Temperature Variations In The Dayside Magnetosheath And Their Dependence On Ion-Scale Magnetic Structures: Themis Statistics And Measurements By Mms, A. P. Dimmock, A. Osmane, T. I. Pulkkinen, K. Nykyri, E. Kilpua Jun 2017

Temperature Variations In The Dayside Magnetosheath And Their Dependence On Ion-Scale Magnetic Structures: Themis Statistics And Measurements By Mms, A. P. Dimmock, A. Osmane, T. I. Pulkkinen, K. Nykyri, E. Kilpua

Publications

The magnetosheath contains an array of waves, instabilities, and nonlinear magnetic structures which modify global plasma properties by means of various wave-particle interactions. The present work demonstrates that ion-scale magnetic field structures (∼0.2–0.5 Hz) observed in the dayside magnetosheath are statistically correlated to ion temperature changes on orders 10–20% of the background value. In addition, our statistical analysis implies that larger temperature changes are in equipartition to larger amplitude magnetic structures. This effect was more pronounced behind the quasi-parallel bow shock and during faster solar wind speeds. The study of two separate intervals suggests that this effect can result from …

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Exchange Of Polar Lipids From Adults To Neonates In Daphnia Magna: Perturbations In Sphingomyelin Allocation By Dietary Lipids And Environmental Toxicants, Namrata Sengupta, Delaney C. Reardon, Patrick D. Gerard, William S. Baldwin May 2017

Exchange Of Polar Lipids From Adults To Neonates In Daphnia Magna: Perturbations In Sphingomyelin Allocation By Dietary Lipids And Environmental Toxicants, Namrata Sengupta, Delaney C. Reardon, Patrick D. Gerard, William S. Baldwin

Publications

Because xenosensing nuclear receptors are also lipid sensors that regulate lipid allocation, we hypothesized that toxicant-induced modulation of HR96 activity would alter lipid profiles and the balance between adult survival and neonate production following exposure in Daphnia magna. Adult daphnids were exposed to unsaturated fatty acid- and toxicant- activators or inhibitors of HR96 and later starved to test whether chemical exposure altered allocation toward survival or reproduction. The HR96 activators, linoleic acid and atrazine, decreased reproduction as expected with concomitant changes in the expression of HR96 regulated genes such as magro. The HR96 inhibitors, docosahexaenoic acid (DHA) and triclosan, …

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Moliere: Automatic Biomedical Hypothesis Generation System, Justin Sybrandt, Michael Shtutman, Ilya Safro May 2017

Moliere: Automatic Biomedical Hypothesis Generation System, Justin Sybrandt, Michael Shtutman, Ilya Safro

Publications

Hypothesis generation is becoming a crucial time-saving technique which allows biomedical researchers to quickly discover implicit connections between important concepts. Typically, these systems operate on domain-specific fractions of public medical data. MOLIERE, in contrast, utilizes information from over 24.5 million documents. At the heart of our approach lies a multi-modal and multi-relational network of biomedical objects extracted from several heterogeneous datasets from the National Center for Biotechnology Information (NCBI). These objects include but are not limited to scientific papers, keywords, genes, proteins, diseases, and diagnoses. We model hypotheses using Latent Dirichlet Allocation applied on abstracts found near shortest paths discovered …

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