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1. MASER: A Science Ready Toolbox for Low Frequency Radio Astronomy

Author

Baptiste Cecconi, Alan Loh, Pierre Le Sidaner, Renaud Savalle, Xavier Bonnin, Quynh Nhu Nguyen, Sonny Lion, Albert Shih, Stéphane Aicardi, Philippe Zarka, Corentin Louis, Andrée Coffre, Laurent Lamy, Laurent Denis, Jean-Mathias Grießmeier, Jeremy Faden, Chris Piker, Nicolas André, Vincent Génot, Stéphane Erard, Joseph N. Mafi, Todd A. King, Jim Sky, and Markus Demleitner

Subjects
radio astronomy, tools, interoperability, Science (General), Q1-390
Abstract

MASER (Measurements, Analysis, and Simulation of Emission in the Radio range) is a comprehensive infrastructure dedicated to time-dependent low frequency radio astronomy (up to about 50 MHz). The main radio sources observed in this spectral range are the Sun, the magnetized planets (Earth, Jupiter, Saturn), and our Galaxy, which are observed either from ground or space. Ground observatories can capture high resolution data streams with a high sensitivity. Conversely, space-borne instruments can observe below the ionospheric cut-off (at about 10 MHz) and can be placed closer to the studied object. Several tools have been developed in the last decade for sharing space physics data. Data visualization tools developed by various institutes are available to share, display and analyse space physics time series and spectrograms. The MASER team has selected a sub-set of those tools and applied them to low frequency radio astronomy. MASER also includes a Python software library for reading raw data from agency archives.

Published
2020
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2. Automated Static Magnetic Cleanliness Screening for the TRACERS Small-Satellite Mission

Author

Cole J. Dorman, Chris Piker, and David M. Miles

Subjects
Physics::Space Physics
Abstract

The Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) Small Explorers mission requires high-fidelity magnetic field measurements for its magnetic reconnection science objectives and for its technology demonstration payload MAGnetometers for Innovation and Capability (MAGIC). TRACERS needs to minimize the local magnetic noise through a magnetic cleanliness program such that the stray fields from the spacecraft and its instruments do not distort the local geophysical magnetic field of interest. Here we present an automated magnetic screening apparatus and procedure to enable technicians to routinely and efficiently measure the magnetic dipole moments of potential flight parts to determine whether they are suitable for spaceflight. This procedure is simple, replicable, and accurate down to a dipole moment of 1.59 × 10-3 N m T-1. It will be used to screen parts for the MAGIC instrument and other subsystems of the TRACERS satellite mission to help ensure magnetically clean measurements on-orbit.

Published
2022

3. Plasma waves in the inner Jovian magnetosphere at low to mid-latitudes

Author

John E. C. Connerney, Jeremy Faden, Darrelle Wilkinson, Ali Sulaiman, Barry Mauk, George Hospodarsky, S. S. Elliott, William S. Kurth, Chris Piker, Frederic Allegrini, John Menietti, and Scott Bolton

Subjects
Physics, Middle latitudes, Physics::Space Physics, Astronomy, Magnetosphere, Astrophysics::Earth and Planetary Astrophysics, Plasma, Jovian
Abstract

Juno's highly eccentric polar orbit was designed to provide the first measurements at low altitudes over the poles to explore Jupiter’s polar magnetosphere and auroras. Orbit precession moves the initially equatorial perijove to higher northern latitudes at a rate of about one degree per orbit. One result of the precession is that Juno crosses the equator at decreasing radial distances during the inbound portion of the orbit. Recently, Juno has crossed the magnetic equator at distances of 10 Jovian radii (RJ) and less. Voyager and Galileo observations have shown the magnetic equator inside of 10 RJ to be the site of numerous plasma wave phenomena including whistler-mode hiss, chorus, electron cyclotron harmonics and upper hybrid bands. In addition, this is the location of the plasma sheet at the outer edge of the Io and Europa torii. The Juno orbit, with its near-polar inclination carries the spacecraft through this intriguing region to higher latitudes. This paper examines the evolution of whistler-mode chorus and hiss as well as electron cyclotron waves from the magnetic equator to higher latitudes. While there are now statistical studies of electromagnetic waves at intermediate latitudes based on Galileo and Juno observations, this paper is designed to show details of these wave phenomena utilizing the Juno Waves instrument’s burst mode for high resolution. Each of these wave phenomena has the potential to interact with the electrons in the inner magnetosphere and cause pitch-angle scattering and/or acceleration, so they are important in the flow of mass and energy through the Jovian system.

Published
2021

4. MASER: A Science Ready Toolbox for Low Frequency Radio Astronomy

Author

Alan Loh, Baptiste Cecconi, J. Sky, Laurent Denis, Pierre Le Sidaner, Vincent Génot, Xavier Bonnin, Renaud Savalle, Joseph N. Mafi, Stéphane Erard, A. Coffre, Stéphane Aicardi, Corentin K. Louis, Chris Piker, Sonny Lion, Quynh Nhu Nguyen, P. Zarka, Jeremy Faden, Nicolas André, Markus Demleitner, Jean-Mathias Grießmeier, Laurent Lamy, Todd King, Albert Y. Shih, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), CNRS-INSU : through ASOV., European Project: 871149,EPN2024-RI, European Project: 654208,H2020,H2020-INFRAIA-2014-2015,EPN2020-RI(2015), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, Computer science, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, interoperability, Low frequency, radio astronomy, 7. Clean energy, 01 natural sciences, law.invention, Jupiter, law, Planet, Saturn, Computer Science (miscellaneous), Maser, lcsh:Science (General), Instrumentation and Methods for Astrophysics (astro-ph.IM), 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Radio astronomy, Tools, Interoperability, 05 social sciences, Astronomy, Space physics, Galaxy, Computer Science Applications, [SDU]Sciences of the Universe [physics], tools, 0509 other social sciences, Ionosphere, Astrophysics - Instrumentation and Methods for Astrophysics, 050904 information & library sciences, Astrophysics - Earth and Planetary Astrophysics, lcsh:Q1-390
Abstract

MASER (Measurements, Analysis, and Simulation of Emission in the Radio range) is a comprehensive infrastructure dedicated to time-dependent low frequency radio astronomy (up to about 50 MHz). The main radio sources observed in this spectral range are the Sun, the magnetized planets (Earth, Jupiter, Saturn), and our Galaxy, which are observed either from ground or space. Ground observatories can capture high resolution data streams with a high sensitivity. Conversely, space-borne instruments can observe below the ionospheric cut-off (at about 10 MHz) and can be placed closer to the studied object. Several tools have been developed in the last decade for sharing space physics data. Data visualization tools developed by various institutes are available to share, display and analyse space physics time series and spectrograms. The MASER team has selected a sub-set of those tools and applied them to low frequency radio astronomy. MASER also includes a Python software library for reading raw data from agency archives., Submitted to Data Science Journal special issue after PV2018 conference

Published
2020

5. The Juno Waves Investigation

Author

D. L. Kirchner, Chris Piker, T. F. Averkamp, W. T. Robison, P. Zarka, George Hospodarsky, B. T. Mokrzycki, M. Sampl, William S. Kurth, University of Iowa [Iowa City], Department of Physics and Astronomy [Iowa City], Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], Physics, Solar System, 010504 meteorology & atmospheric sciences, Waves in plasmas, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Magnetosphere, Astronomy and Astrophysics, 7. Clean energy, 01 natural sciences, Astrobiology, Jupiter, Atmosphere, Planetary science, Exploration of Jupiter, Space and Planetary Science, Physics::Space Physics, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Magnetosphere of Jupiter, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

Jupiter is the source of the strongest planetary radio emissions in the solar system. Variations in these emissions are symptomatic of the dynamics of Jupiter’s magnetosphere and some have been directly associated with Jupiter’s auroras. The strongest radio emissions are associated with Io’s interaction with Jupiter’s magnetic field. In addition, plasma waves are thought to play important roles in the acceleration of energetic particles in the magnetosphere, some of which impact Jupiter’s upper atmosphere generating the auroras. Since the exploration of Jupiter’s polar magnetosphere is a major objective of the Juno mission, it is appropriate that a radio and plasma wave investigation is included in Juno’s payload. This paper describes the Waves instrument and the science it is to pursue as part of the Juno mission.

Published
2017

7. The Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) on RBSP

Author

Mario H. Acuña, Chris Piker, D. Bodet, John E. P. Connerney, Robert J. MacDowall, J. Odom, J. R. Phillips, Scott R. Bounds, S. L. Remington, B. T. Mokrzycki, Douglas E. Rowland, D. Mark, R. T. Dvorsky, Craig Kletzing, D. Crawford, Ondrej Santolik, Roy B. Torbert, R. A. Johnson, Charles W. Smith, R. Schnurr, Vania K. Jordanova, J. Howard, T. F. Averkamp, G. Needell, D. Sheppard, George Hospodarsky, Richard M. Thorne, J. Tyler, M. Chutter, J. S. Dolan, William S. Kurth, R. F. Pfaff, and D. L. Kirchner

Subjects
Physics, business.industry, Suite, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Space weather, symbols.namesake, Acceleration, Planetary science, Space and Planetary Science, Van Allen radiation belt, Physics::Space Physics, Key (cryptography), symbols, Van Allen Probes, Astrophysics::Earth and Planetary Astrophysics, Electronics, Aerospace engineering, business, Remote sensing
Abstract

The Electric and Magnetic Field Instrument and Integrated Science (EMFISIS) investigation on the NASA Radiation Belt Storm Probes (now named the Van Allen Probes) mission provides key wave and very low frequency magnetic field measurements to understand radiation belt acceleration, loss, and transport. The key science objectives and the contribution that EMFISIS makes to providing measurements as well as theory and modeling are described. The key components of the instruments suite, both electronics and sensors, including key functional parameters, calibration, and performance, demonstrate that EMFISIS provides the needed measurements for the science of the RBSP mission. The EMFISIS operational modes and data products, along with online availability and data tools provide the radiation belt science community with one the most complete sets of data ever collected.

Published
2013

8. The influence of Titan on Saturn kilometric radiation

Author

Chris Piker, J. D. Menietti, Baptiste Cecconi, and Shengyi Ye

Subjects
Atmospheric Science, Waves in plasmas, Field line, Direction finding, lcsh:QC801-809, Astronomy, Electron precipitation, Geology, Astronomy and Astrophysics, lcsh:QC1-999, Astrobiology, lcsh:Geophysics. Cosmic physics, symbols.namesake, Space and Planetary Science, Midnight, Local time, Magnetosphere of Saturn, Earth and Planetary Sciences (miscellaneous), symbols, lcsh:Q, lcsh:Science, Titan (rocket family), lcsh:Physics
Abstract

Previous studies have shown that the occurrence probability of Saturn Kilometric Radiation (SKR) appears to be influenced by the local time of Titan. Using a more extensive set of data than the original study, we confirm the correlation of higher occurrence probability of SKR when Titan is located near local midnight. In addition, the direction finding capability of the Cassini Radio Plasma Wave instrument (RPWS) is used to determine if this radio emission emanates from particular source regions. We find that most source regions of SKR are located in the mid-morning sector of local time even when Titan is located near midnight. However, some emission does appear to have a source in the Saturnian nightside, consistent with electron precipitation from field lines that have recently mapped to near Titan.

Published
2010

9. CT Metrics of Airway Disease and Emphysema in Severe COPD

Author

James Walter, David Godwin, Joyce Canterbury, Thomas E. Hartman, Yen Pin Chiang, Jeanne Smith, John J. Reilly, Hope Livingston, Abby M. Krichman, Mahasti Rittinger, Karma L. Kreizenbeck, Kymberley Anable, Ameena Al-Amin, Colleen Witt, Karen McVearry, Claude Deschamps, Selim M. Arcasoy, Liz Roessler, James K. Stoller, Yahya M. Berkmen, Paul J. Friedman, Enrique Fernandez, Laura Kotler-Klein, Chris Piker, Robert E. Hyatt, Mark J. Krasna, Priscilla McCreight, Jo Anna Baldwin, Jennifer M Lamb, Francisco Alvarez, Janet R. Maurer, Rodney Simcox, Gerald O'Brien, Iris Moskowitz, Marianne C. Fahs, Judd Gurney, A. Mark Fendrick, Mike Mantinaos, Sanjay Kalra, Robert M. Kaplan, Kevin R. Flaherty, Timothy Gilbert, James K. Garrett, Kathy Mieras, Kapreena Owens, Trina Limberg, Patricia Belt, Rolf D. Hubmayr, Roger Barnette, James Carter, Phillip M. Boiselle, Brian Woodcock, Anne Marie Kuzma, Brian F. Mullan, Dean Follmann, Mary Ellen Kleinhenz, Judith Harle, Ubaldo J. Martin, Bonnie Edwards, Fernando I. Martinez, Sandy Do, Alejandro A. Diaz, F.C. Sciurba, William Russell, David J. Sugarbaker, Theresa Alcorn, Susan Borosh, Patricia McDowell, Carolyn Wheeler, Blake Wood, Edwin K. Silverman, Alan J. Moskowitz, John F. Plankeel, William F. Bria, Susan Clark, Patricia Ward, Scott D. Ramsey, Barry J. Make, David H Kupferberg, Chinh T. Q. Nguyen, Stanley Aukberg, Elisabeth L. George, Steven Piantadosi, Geoffrey McLennan, Carl D. Mottram, Martin Zamora, Marvin Pomerantz, Ella A. Kazerooni, Jennifer Propst, Bessie Kachulis, Carol Fanning, Valentina Yegyan, Kenneth Silver, James P. Kiley, Sabine Duffy, David H. Harpole, Junfeng Guo, Donald C. Oxorn, Andrew L. Ries, Paramjit Gill, Bruce H. Culver, Todd M. Officer, Catherine Wood Larsen, John Hansen-Flaschen, Patrick Ross, Mindi Steiger, Lori Hanson, Rose Butanda, Paul F. Simonelli, Neil W. Brister, Amy Chong, Charles L. White, Eric A. Jensen, Cynthia Raymond, Mark K. Ferguson, Moulay Meziane, Mary Milburn-Barnes, James D. Luketich, Douglas E. Wood, A. John McSweeny, Woo Jin Kim, Kim Stavrolakes, John A. Waldhausen, Gregory L. Aughenbaugh, Chul Kwak, Sara L. Bartling, Joan Osterloh, Larry R. Kaiser, John S. Howe, Michael I. Lewis, Andrew Bowdle, Mark A. Gerhardt, Richard O'Connell, Brian R. Lawlor, Neil R. MacIntyre, David A. Lynch, Milton Joyner, Louie Boitano, James P. Utz, Everett Hood, Paul J. Smith, Joshua O. Benditt, John Apostolakis, Frances L. Brogan, Robert McKenna, Berend Mets, Phyllis Dibbern, Kevin Carney, Joan M. Lacomis, Kevin McCarthy, A. Laurie Shroyer, Mitchell K. O’Shea, Barry Make, Dora Greene, Janice Willey, Catherine Ramirez, Gwendolyn B. Vance, Philip R. Karsell, David DeMets, Angela DiMango, Peter Rising, Erik J. Kraenzler, Michael F. Keresztury, Laurie Ney Silfies, Michael Magliocca, Vivian Knieper, Betsy Ann Bozzarello, Marlene Edgar, Madelina Lorenzon, Deb Andrist, Sophia Chatziioannou, Darryl Atwell, Sally Frese, Ruth Etzioni, Stephen I. Marglin, Maria Shiau, Thomas Schroeder, Vincent J. Carey, Vladmir Formanek, Robert Levine, Cindy Chwalik, David Rittinger, Kenneth Martay, Brett A. Simon, Nancy Kurokawa, Anne L. Fuhlbrigge, Peter J. Julien, Michelle T. Toshima, Sean D. Sullivan, Joanne Deshler, Margaret Wu, Anthony Norris, David A. Lipson, Scott J. Swanson, Diane Lockhart, Omar A. Minai, Joseph l. Reeves-Viets, Raed A. Dweik, Keith S. Naunheim, Angela Delsing, Minnie Ellisor, Jane Whalen-Price, Victor F. Tapson, Leonard Rossoff, Susan M. Peterson, Deborah Nowakowski, David M. Shade, Susanne Snedeker, Susan Craemer, Anne Marie G. Sykes, Jennifer Norten, Manmohan S. Biring, Diane C. Strollo, Beth Elliot, Kedren Williams, Heather Sheaffer, Sheila Shearer, Robert P. Hoffman, Robert Quaife, J. Mendez, Donald A. Mahler, Janice Cook-Granroth, Scott Marlow, Zab Mosenifar, Malcolm M. DeCamp, Paul J. Christensen, Rosetta Jackson, Wissam Chatila, Robert Schilz, Glenda DeMercado, Peter B. O'Donovan, Kimberly Dubose, Robert J. Keenan, Satoshi Furukawa, Theodore Kopp, Gerald T. Ayres, Betty Collison, Stephen J. Swensen, Jennifer Stone-Wynne, Nicole Jenson, Stanley S. Siegelman, Tina Bees, Owen B. Wilson, R. Duane Davis, Pierre A. DeVilliers, Marcia Katz, Carolyn M. Clancy, Eddie L. Hoover, Bryan Benedict, Karen Kirsch, Philip M. Hartigan, Simon C. Body, Mark Stafford-Smith, David A. Zisman, Jeanne M. Hoffman, Fernando J. Martinez, Clarence Weir, Jeffrey D. Edelman, William Stanford, Zab Mohsenifar, Michael P. Donahoe, Michele Donithan, Catherine A. Meldrum, William A. Slivka, Lori Zaremba, Michael W. Smith, Martin D. Abel, Robert B Gerber, Sarah Hooper, Steven M. Scharf, Karen A. Hanson, Katherine P. Grichnik, J. Sanford Schwartz, Margaret L. Snyder, Charles J. Hearn, Joe Chin, Tammy Ojo, Gregory D.N. Pearson, Vera Edmonds, George R. Washko, Christine Young, Jennifer Minkoff-Rau, Ron Daniele, Chun Yip, Gregory L. Foster, Harold I. Palevsky, Joan E. Sexton, Dev Pathak, Pamela Fox, Paul E. Kazanjian, Karen King, Jacqueline Pfeffer, Imran Nizami, Judith Wagner, Catherine Wrona, John H. M. Austin, Karla Conejo-Gonzales, Sharon Bendel, Amir Sharafkhaneh, Carol Geaga, Denise Vilotijevic, Thomas H. Sisson, Steven H. Sheingold, Ryan Colvin, Elaine Baker, Karen Collins, Charles F. Emery, Mark Ginsburg, Abass Alavi, David D. Frankville, Joseph M. Reinhardt, Jan Drake, John M. Travaline, Rafael Espada, Kathy Lautensack, Leslie E. Quint, Jeffrey T. Chapman, Rosemary Lann, Steven M. Berkowitz, Alice L. Sternberg, Thurman Gillespy, Nadia Howlader, Frank J. Papatheofanis, Robert Frantz, Manuel L. Brown, Sarah Shirey, Yvonne Meli, Andra E. Ibrahim, Patricia A. Jellen, Rebecca Crouch, Warren B. Gefter, Michael J. Reardon, Jonathan B. Orens, Neal S. Kleiman, Marilyn L. Moy, Daniel L. Miller, Julie Fuller, Reuben M. Cherniack, Claudette Sikora, Lynn Bosco, Harry Handelsman, R. Edward Coleman, Judith M. Aronchick, James Tonascia, Delmar J. Gillespie, Patricia Berkoski, David P. Kapelanski, Cesar A. Keller, Amanda L. Blackford, Charles C. Miller, Kelly M. Campbell, Jill Meinert, Carl R. Fuhrman, Gordon R. Bernard, Connie Hudson, Roger Russell, Lewis Poole, Dale Williams, Magdy Younes, Shing Lee, Steven L. Sax, Martin Carlos, Diane C. Saunders, John Dodge, Matthew N. Bartels, Amy Jahn, Karen Taylor, Gregg L Ruppel, Wallace T. Miller, Mary Gilmartin, Tanisha Carino, Alfred P. Fishman, Gerene Bauldoff, Frank C. Sciurba, Gerard J. Criner, John Haddad, Mark D. Iannettoni, Terri Durr, Gordon F. Harms, Susan Golden, Norman E. Torres, Lisa Geyman, Alan Hibbit, Paul Rysso, Gilbert E. D'Alonzo, Henry E. Fessler, Mark L. Van Natta, Peter Wahl, James H. Harrell, Willard Chamberlain, Roger D. Yusen, Boleyn Hammel, Dawn E. Sassi-Dambron, Mark S. Allen, Jennifer Cutler, Shangqian Qi, Susan Rinaldo-Gallo, John D. Newell, June Hart, Raúl San José Estépar, Kerri McKeon, Staci Opelman, Eric S. Edell, Kathy Winner, Joe R. Rodarte, Mark A. King, Eric A. Hoffman, Laura A. Wilson, Phil Cagle, Jennifer Meyers, Kristin Berry, Mark P. Steele, Katherine Hale, Peter Barnard, Charles Soltoff, Melissa Weeks, Arfa Khan, Cary Stolar, Jeanine P. Wiener-Kronish, Jeannie Ricketts, Nancy Battaglia, Francine L. Jacobson, Satish G. Jhingran, Robert B. Teague, Mary Louise Dempsey, Leighton Chan, Philip T. Diaz, David Hicks, David E. Midthun, Charlene Levine, Andetta R. Hunsaker, Tomeka Simon, Jered Sieren, Susan Lubell, Scott A. Schartel, H P McAdams, Francis Cordova, Kris Bradt, Jeffery J. Johnson, Kenneth White, Mercedes True, Erin A. Sullivan, Byron Thomashow, Gail Weinmann, Robert A. Wise, Donna Tsang, Robert M. Kotloff, Atul C. Mehta, Gregory Tino, and Angela Wurster

Subjects
Adult, Male, Pulmonary and Respiratory Medicine, medicine.medical_specialty, Pathology, Critical Care and Intensive Care Medicine, Risk Assessment, Sensitivity and Specificity, Severity of Illness Index, Cohort Studies, Pulmonary Disease, Chronic Obstructive, Predictive Value of Tests, Forced Expiratory Volume, Internal medicine, medicine, Humans, Lung volumes, Respiratory system, Aged, Probability, Original Research, Analysis of Variance, Univariate analysis, COPD, business.industry, Total Lung Capacity, Respiratory disease, Middle Aged, respiratory system, Airway obstruction, medicine.disease, Respiratory Function Tests, respiratory tract diseases, Airway Obstruction, Dyspnea, medicine.anatomical_structure, Pulmonary Emphysema, Multivariate Analysis, Cardiology, Female, Pulmonary Ventilation, Tomography, X-Ray Computed, Cardiology and Cardiovascular Medicine, business, Airway, Respiratory tract
Abstract

Background CT scan measures of emphysema and airway disease have been correlated with lung function in cohorts of subjects with a range of COPD severity. The contribution of CT scan-assessed airway disease to objective measures of lung function and respiratory symptoms such as dyspnea in severe emphysema is less clear. Methods Using data from 338 subjects in the National Emphysema Treatment Trial (NETT) Genetics Ancillary Study, densitometric measures of emphysema using a threshold of −950 Hounsfield units (%LAA-950) and airway wall phenotypes of the wall thickness (WT) and the square root of wall area (SRWA) of a 10-mm luminal perimeter airway were calculated for each subject. Linear regression analysis was performed for outcome variables FEV 1 and percent predicted value of FEV 1 with CT scan measures of emphysema and airway disease. Results In univariate analysis, there were significant negative correlations between %LAA-950 and both the WT ( r = −0.28, p = 0.0001) and SRWA ( r = −0.19, p = 0.0008). Airway wall thickness was weakly but significantly correlated with postbronchodilator FEV 1 % predicted (R = −0.12, p = 0.02). Multivariate analysis showed significant associations between either WT or SRWA (β = −5.2, p = 0.009; β = −2.6, p = 0.008, respectively) and %LAA-950 (β = −10.6, p = 0.03) with the postbronchodilator FEV 1 % predicted. Male subjects exhibited significantly thicker airway wall phenotypes (p = 0.007 for WT and p = 0.0006 for SRWA). Conclusions Airway disease and emphysema detected by CT scanning are inversely related in patients with severe COPD. Airway wall phenotypes were influenced by gender and associated with lung function in subjects with severe emphysema.

Published
2009

10. Evaluation of Lung MDCT Nodule Annotation Across Radiologists and Methods

Author

David F. Yankelevitz, Anthony P. Reeves, Barbara Y. Croft, Heber MacMahon, Adam Starkey, Laurence P. Clarke, Chris Piker, Daniel Max, Eric A. Hoffman, Samuel G. Armato, Brian F. Mullan, Geoffrey McLennan, David Gur, Richie C. Pais, Peyton H. Bland, Junfeng Guo, Ella A. Kazerooni, Timothy D. Johnson, Michael F. McNitt-Gray, Denise R. Aberle, David Qing, Claudia I. Henschke, Gary E. Laderach, Edwin J. R. van Beek, and Charles R. Meyer

Subjects
medicine.medical_specialty, Lung Neoplasms, Sensitivity and Specificity, Standard deviation, Pattern Recognition, Automated, Professional Competence, Artificial Intelligence, Physicians, Image Interpretation, Computer-Assisted, Task Performance and Analysis, medicine, Humans, Radiology, Nuclear Medicine and imaging, Observer Variation, Solitary pulmonary nodule, business.industry, Reproducibility of Results, Solitary Pulmonary Nodule, Nodule (medicine), Variance (accounting), medicine.disease, Random effects model, Metric (unit), Radiology, Tomography, medicine.symptom, Tomography, X-Ray Computed, business, Volume (compression)
Abstract

RATIONALE AND OBJECTIVES: Integral to the mission of the National Institutes of Health-sponsored Lung Imaging Database Consortium is the accurate definition of the spatial location of pulmonary nodules. Because the majority of small lung nodules are not resected, a reference standard from histopathology is generally unavailable. Thus assessing the source of variability in defining the spatial location of lung nodules by expert radiologists using different software tools as an alternative form of truth is necessary.MATERIALS AND METHODS: The relative differences in performance of six radiologists each applying three annotation methods to the task of defining the spatial extent of 23 different lung nodules were evaluated. The variability of radiologists' spatial definitions for a nodule was measured using both volumes and probability maps (p-map). Results were analyzed using a linear mixed-effects model that included nested random effects.RESULTS: Across the combination of all nodules, volume and p-map model parameters were found to be significant at P CONCLUSION: Radiologists represent the major source of variance as compared with drawing tools independent of drawing metric used. Although the random noise component is larger for the p-map analysis than for volume estimation, the p-map analysis appears to have more power to detect differences in radiologist-method combinations. The standard deviation of the volume measurement task appears to be proportional to nodule volume.

Published
2006

11. The Lung Image Database Consortium (LIDC) Data Collection Process for Nodule Detection and Annotation

Author

Chris Piker, David Qing, Matthew S. Brown, John Freymann, Edwin J. R. van Beek, Charles R. Meyer, Anthony P. Reeves, Denise R. Aberle, Zaid J. Towfic, Geoffrey McLennan, David F. Yankelevitz, Laurence P. Clarke, Richie C. Pais, Ella A. Kazerooni, Michael F. McNitt-Gray, Gary E. Laderach, Peyton H. Bland, Barbara Y. Croft, Roger Engelmann, Heber MacMahon, Samuel G. Armato, and Junfeng Guo

Subjects
medicine.medical_specialty, Solitary pulmonary nodule, Data collection, business.industry, Radiography, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, MEDLINE, medicine.disease, Article, Annotation, ComputingMethodologies_PATTERNRECOGNITION, Computer-aided diagnosis, Image database, Medical imaging, medicine, Radiology, Nuclear Medicine and imaging, Medical physics, Radiology, business
Abstract

RATIONALE AND OBJECTIVES: The Lung Image Database Consortium (LIDC) is developing a publicly available database of thoracic computed tomography (CT) scans as a medical imaging research resource to promote the development of computer-aided detection or characterization of pulmonary nodules. To obtain the best estimate of the location and spatial extent of lung nodules, expert thoracic radiologists reviewed and annotated each scan. Because a consensus panel approach was neither feasible nor desirable, a unique two-phase, multicenter data collection process was developed to allow multiple radiologists at different centers to asynchronously review and annotate each CT scan. This data collection process was also intended to capture the variability among readers.MATERIALS AND METHODS: Four radiologists reviewed each scan using the following process. In the first or "blinded" phase, each radiologist reviewed the CT scan independently. In the second or "unblinded" review phase, results from all four blinded reviews were compiled and presented to each radiologist for a second review, allowing the radiologists to review their own annotations together with the annotations of the other radiologists. The results of each radiologist's unblinded review were compiled to form the final unblinded review. An XML-based message system was developed to communicate the results of each reading.RESULTS: This two-phase data collection process was designed, tested, and implemented across the LIDC. More than 500 CT scans have been read and annotated using this method by four expert readers; these scans either are currently publicly available at http://ncia.nci.nih.gov or will be in the near future.CONCLUSIONS: A unique data collection process was developed, tested, and implemented that allowed multiple readers at distributed sites to asynchronously review CT scans multiple times. This process captured the opinions of each reader regarding the location and spatial extent of lung nodules.

Published
2007

12. A survey of Galileo plasma wave instrument observations of Jovian whistler-mode chorus

Author

D. A. Gurnett, Chris Piker, George Hospodarsky, Richard B. Horne, J. D. Menietti, and J. B. Groene

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Magnetic dip, Astrophysics, 01 natural sciences, Jovian, Relativistic particle, Jupiter, symbols.namesake, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), lcsh:Science, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Waves in plasmas, lcsh:QC801-809, Astronomy, Geology, Astronomy and Astrophysics, lcsh:QC1-999, Particle acceleration, lcsh:Geophysics. Cosmic physics, 13. Climate action, Space and Planetary Science, Van Allen radiation belt, Physics::Space Physics, symbols, lcsh:Q, Astrophysics::Earth and Planetary Astrophysics, Galileo (vibration training), lcsh:Physics
Abstract

A survey of plasma wave observations at Jupiter obtained by the plasma wave instrument on board the Galileo spacecraft is presented. The observations indicate that chorus emissions are observed commonly in the Jovian magnetosphere near the magnetic equator in the approximate radial range 6

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