12 results
6 - Re-envisioning Fire and Vegetation Feedbacks
- Edited by Kevin Speer, Florida State University, Scott Goodrick
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- Book:
- Wildland Fire Dynamics
- Published online:
- 16 June 2022
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- 30 June 2022, pp 156-182
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Summary
This chapter describes the interactions between three-dimensional fuel metrics, intrinsic fuel properties, plant functional traits, and physical characteristics of fuels that inform a new understanding of fire and vegetation feedbacks. The integration of these themes introduces a new synthetic model of fire–vegetation feedbacks. Interrelated concepts of fire, fluid flow, functional traits, and computational fluid dynamics fire behavior models are discussed within the synthetic model framework.
Coronavirus disease 2019 (COVID-19) research agenda for healthcare epidemiology
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- Lona Mody, Ibukunoluwa C. Akinboyo, Hilary M. Babcock, Werner E. Bischoff, Vincent Chi-Chung Cheng, Kathleen Chiotos, Kimberly C. Claeys, K. C. Coffey, Daniel J. Diekema, Curtis J. Donskey, Katherine D. Ellingson, Heather M. Gilmartin, Shruti K. Gohil, Anthony D. Harris, Sara C. Keller, Eili Y. Klein, Sarah L. Krein, Jennie H Kwon, Adam S. Lauring, Daniel J. Livorsi, Eric T. Lofgren, Katreena Merrill, Aaron M. Milstone, Elizabeth A. Monsees, Daniel J. Morgan, Luci P. Perri, Christopher D. Pfeiffer, Clare Rock, Sanjay Saint, Emily Sickbert-Bennett, Felicia Skelton, Katie J. Suda, Thomas R. Talbot, Valerie M. Vaughn, David J. Weber, Timothy L. Wiemken, Mohamed H. Yassin, Matthew J. Ziegler, Deverick J. Anderson
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 43 / Issue 2 / February 2022
- Published online by Cambridge University Press:
- 25 January 2021, pp. 156-166
- Print publication:
- February 2022
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This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to coronavirus disease 2019 (COVID-19) with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplementary materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
The Qualitative Transparency Deliberations: Insights and Implications
- Alan M. Jacobs, Tim Büthe, Ana Arjona, Leonardo R. Arriola, Eva Bellin, Andrew Bennett, Lisa Björkman, Erik Bleich, Zachary Elkins, Tasha Fairfield, Nikhar Gaikwad, Sheena Chestnut Greitens, Mary Hawkesworth, Veronica Herrera, Yoshiko M. Herrera, Kimberley S. Johnson, Ekrem Karakoç, Kendra Koivu, Marcus Kreuzer, Milli Lake, Timothy W. Luke, Lauren M. MacLean, Samantha Majic, Rahsaan Maxwell, Zachariah Mampilly, Robert Mickey, Kimberly J. Morgan, Sarah E. Parkinson, Craig Parsons, Wendy Pearlman, Mark A. Pollack, Elliot Posner, Rachel Beatty Riedl, Edward Schatz, Carsten Q. Schneider, Jillian Schwedler, Anastasia Shesterinina, Erica S. Simmons, Diane Singerman, Hillel David Soifer, Nicholas Rush Smith, Scott Spitzer, Jonas Tallberg, Susan Thomson, Antonio Y. Vázquez-Arroyo, Barbara Vis, Lisa Wedeen, Juliet A. Williams, Elisabeth Jean Wood, Deborah J. Yashar
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- Journal:
- Perspectives on Politics / Volume 19 / Issue 1 / March 2021
- Published online by Cambridge University Press:
- 06 January 2021, pp. 171-208
- Print publication:
- March 2021
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In recent years, a variety of efforts have been made in political science to enable, encourage, or require scholars to be more open and explicit about the bases of their empirical claims and, in turn, make those claims more readily evaluable by others. While qualitative scholars have long taken an interest in making their research open, reflexive, and systematic, the recent push for overarching transparency norms and requirements has provoked serious concern within qualitative research communities and raised fundamental questions about the meaning, value, costs, and intellectual relevance of transparency for qualitative inquiry. In this Perspectives Reflection, we crystallize the central findings of a three-year deliberative process—the Qualitative Transparency Deliberations (QTD)—involving hundreds of political scientists in a broad discussion of these issues. Following an overview of the process and the key insights that emerged, we present summaries of the QTD Working Groups’ final reports. Drawing on a series of public, online conversations that unfolded at www.qualtd.net, the reports unpack transparency’s promise, practicalities, risks, and limitations in relation to different qualitative methodologies, forms of evidence, and research contexts. Taken as a whole, these reports—the full versions of which can be found in the Supplementary Materials—offer practical guidance to scholars designing and implementing qualitative research, and to editors, reviewers, and funders seeking to develop criteria of evaluation that are appropriate—as understood by relevant research communities—to the forms of inquiry being assessed. We dedicate this Reflection to the memory of our coauthor and QTD working group leader Kendra Koivu.1
Cotton Stage of Growth Determines Sensitivity to 2,4-D
- Seth A. Byrd, Guy D. Collins, A. Stanley Culpepper, Darrin M. Dodds, Keith L. Edmisten, David L. Wright, Gaylon D. Morgan, Paul A. Baumann, Peter A. Dotray, Misha R. Manuchehri, Andrea Jones, Timothy L. Grey, Theodore M. Webster, Jerry W. Davis, Jared R. Whitaker, Phillip M. Roberts, John L. Snider, Wesley M. Porter
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- Journal:
- Weed Technology / Volume 30 / Issue 3 / September 2016
- Published online by Cambridge University Press:
- 20 January 2017, pp. 601-610
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The anticipated release of EnlistTM cotton, corn, and soybean cultivars likely will increase the use of 2,4-D, raising concerns over potential injury to susceptible cotton. An experiment was conducted at 12 locations over 2013 and 2014 to determine the impact of 2,4-D at rates simulating drift (2 g ae ha−1) and tank contamination (40 g ae ha−1) on cotton during six different growth stages. Growth stages at application included four leaf (4-lf), nine leaf (9-lf), first bloom (FB), FB + 2 wk, FB + 4 wk, and FB + 6 wk. Locations were grouped according to percent yield loss compared to the nontreated check (NTC), with group I having the least yield loss and group III having the most. Epinasty from 2,4-D was more pronounced with applications during vegetative growth stages. Importantly, yield loss did not correlate with visual symptomology, but more closely followed effects on boll number. The contamination rate at 9-lf, FB, or FB + 2 wk had the greatest effect across locations, reducing the number of bolls per plant when compared to the NTC, with no effect when applied at FB + 4 wk or later. A reduction of boll number was not detectable with the drift rate except in group III when applied at the FB stage. Yield was influenced by 2,4-D rate and stage of cotton growth. Over all locations, loss in yield of greater than 20% occurred at 5 of 12 locations when the drift rate was applied between 4-lf and FB + 2 wk (highest impact at FB). For the contamination rate, yield loss was observed at all 12 locations; averaged over these locations yield loss ranged from 7 to 66% across all growth stages. Results suggest the greatest yield impact from 2,4-D occurs between 9-lf and FB + 2 wk, and the level of impact is influenced by 2,4-D rate, crop growth stage, and environmental conditions.
Impact of methods used to express levels of circulating fatty acids on the degree and direction of associations with blood lipids in humans
- Susan Sergeant, Ingo Ruczinski, Priscilla Ivester, Tammy C. Lee, Timothy M. Morgan, Barbara J. Nicklas, Rasika A. Mathias, Floyd H. Chilton
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- Journal:
- British Journal of Nutrition / Volume 115 / Issue 2 / 28 January 2016
- Published online by Cambridge University Press:
- 30 November 2015, pp. 251-261
- Print publication:
- 28 January 2016
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Numerous studies have examined relationships between disease biomarkers (such as blood lipids) and levels of circulating or cellular fatty acids. In such association studies, fatty acids have typically been expressed as the percentage of a particular fatty acid relative to the total fatty acids in a sample. Using two human cohorts, this study examined relationships between blood lipids (TAG, and LDL, HDL or total cholesterol) and circulating fatty acids expressed either as a percentage of total or as concentration in serum. The direction of the correlation between stearic acid, linoleic acid, dihomo-γ-linolenic acid, arachidonic acid and DHA and circulating TAG reversed when fatty acids were expressed as concentrations v. a percentage of total. Similar reversals were observed for these fatty acids when examining their associations with the ratio of total cholesterol:HDL-cholesterol. This reversal pattern was replicated in serum samples from both human cohorts. The correlations between blood lipids and fatty acids expressed as a percentage of total could be mathematically modelled from the concentration data. These data reveal that the different methods of expressing fatty acids lead to dissimilar correlations between blood lipids and certain fatty acids. This study raises important questions about how such reversals in association patterns impact the interpretation of numerous association studies evaluating fatty acids and their relationships with disease biomarkers or risk.
Contributors
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- By Janice Capel Anderson, S. Wesley Ariarajah, Constantine Belezos, Ian Boxall, Marc Zvi Brettler, Edward Breuer, Daniel Bruno, Mark Chapman, W. T. Dickens, Mark W. Elliott, Eldon Epp, Tassilo Erhardt, Timothy Gorringe, Harriet Harris, Peter C. Hodgson, Leslie Howsam, Werner G. Jeanrond, Scott McLaren, Wayne A. Meeks, Néstor Míguez, Stephen D. Moore, Robert Morgan, Halvor Moxnes, Peter Neuner, Mark Noll, Jorunn Økland, Gaye Ortiz, John Riches, Christopher Rowland, Nicolaas A. Rupke, Edmund J. Rybarczyk, Lamin Sanneh, Constantine Scouteris, R. S. Sugirtharajah, Willard M. Swartley, William R. Telford, David Thompson, Elena Volkova, J. R. Watson, Gerald West, Michael Wheeler, Keith Whitelam
- Edited by John Riches, University of Glasgow
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- The New Cambridge History of the Bible
- Published online:
- 09 June 2015
- Print publication:
- 13 April 2015, pp xi-xii
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Isolation Precautions for Visitors
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- L. Silvia Munoz-Price, David B. Banach, Gonzalo Bearman, Jane M. Gould, Surbhi Leekha, Daniel J. Morgan, Tara N. Palmore, Mark E. Rupp, David J. Weber, Timothy L. Wiemken
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 36 / Issue 7 / July 2015
- Published online by Cambridge University Press:
- 10 April 2015, pp. 747-758
- Print publication:
- July 2015
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Contributors
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- By Andrew Adesman, Lenard A. Adler, Samuel Alperin, Kira E. Armstrong, L. Eugene Arnold, Amy F. T. Arnsten, Russell A. Barkley, Craig W. Berridge, Joseph Biederman, F. Xavier Castellanos, Barbara J. Coffey, Alison M. Cohn, C. Keith Conners, Joan M. Daughton, Stephen V. Faraone, John Fayyad, Lisa G. Hahn, Laura Hans, Elizabeth Hurt, Gagan Joshi, Rahil Jummani, Jesse M. Jun, Ronald C. Kessler, Scott Haden Kollins, Kimberly Kovacs, Christopher J. Kratochvil, Beth Krone, Nicholas Lofthouse, Michael J. Manos, Francis Joseph McClernon, Joel E. Morgan, Nicholas R. Morrison, Sonali Nanayakkara, Jeffrey H. Newcorn, Phillip L. Pearl, Juan D. Pedraza, Guy M. L. Perry, Steven R. Pliszka, Jefferson B. Prince, J. Russell Ramsay, Anthony L. Rostain, David M. Shaw, Mary V. Solanto, Mark A. Stein, Jonathan R. Stevens, Brigette S. Vaughan, Margaret Weiss, Roy E. Weiss, Timothy E. Wilens, Janet Wozniak
- Edited by Lenard A. Adler, New York University School of Medicine, Thomas J. Spencer, Timothy E. Wilens
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- Book:
- Attention-Deficit Hyperactivity Disorder in Adults and Children
- Published online:
- 05 February 2015
- Print publication:
- 08 January 2015, pp vii-x
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- By Frank Andrasik, Melissa R. Andrews, Ana Inés Ansaldo, Evangelos G. Antzoulatos, Lianhua Bai, Ellen Barrett, Linamara Battistella, Nicolas Bayle, Michael S. Beattie, Peter J. Beek, Serafin Beer, Heinrich Binder, Claire Bindschaedler, Sarah Blanton, Tasia Bobish, Michael L. Boninger, Joseph F. Bonner, Chadwick B. Boulay, Vanessa S. Boyce, Anna-Katharine Brem, Jacqueline C. Bresnahan, Floor E. Buma, Mary Bartlett Bunge, John H. Byrne, Jeffrey R. Capadona, Stefano F. Cappa, Diana D. Cardenas, Leeanne M. Carey, S. Thomas Carmichael, Glauco A. P. Caurin, Pablo Celnik, Kimberly M. Christian, Stephanie Clarke, Leonardo G. Cohen, Adriana B. Conforto, Rory A. Cooper, Rosemarie Cooper, Steven C. Cramer, Armin Curt, Mark D’Esposito, Matthew B. Dalva, Gavriel David, Brandon Delia, Wenbin Deng, Volker Dietz, Bruce H. Dobkin, Marco Domeniconi, Edith Durand, Tracey Vause Earland, Georg Ebersbach, Jonathan J. Evans, James W. Fawcett, Uri Feintuch, Toby A. Ferguson, Marie T. Filbin, Diasinou Fioravante, Itzhak Fischer, Agnes Floel, Herta Flor, Karim Fouad, Richard S. J. Frackowiak, Peter H. Gorman, Thomas W. Gould, Jean-Michel Gracies, Amparo Gutierrez, Kurt Haas, C.D. Hall, Hans-Peter Hartung, Zhigang He, Jordan Hecker, Susan J. Herdman, Seth Herman, Leigh R. Hochberg, Ahmet Höke, Fay B. Horak, Jared C. Horvath, Richard L. Huganir, Friedhelm C. Hummel, Beata Jarosiewicz, Frances E. Jensen, Michael Jöbges, Larry M. Jordan, Jon H. Kaas, Andres M. Kanner, Noomi Katz, Matthew S. Kayser, Annmarie Kelleher, Gerd Kempermann, Timothy E. Kennedy, Jürg Kesselring, Fary Khan, Rachel Kizony, Jeffery D. Kocsis, Boudewijn J. Kollen, Hubertus Köller, John W. Krakauer, Hermano I. Krebs, Gert Kwakkel, Bradley Lang, Catherine E. Lang, Helmar C. Lehmann, Angelo C. Lepore, Glenn S. Le Prell, Mindy F. Levin, Joel M. Levine, David A. Low, Marilyn MacKay-Lyons, Jeffrey D. Macklis, Margaret Mak, Francine Malouin, William C. Mann, Paul D. Marasco, Christopher J. Mathias, Laura McClure, Jan Mehrholz, Lorne M. Mendell, Robert H. Miller, Carol Milligan, Beth Mineo, Simon W. Moore, Jennifer Morgan, Charbel E-H. Moussa, Martin Munz, Randolph J. Nudo, Joseph J. Pancrazio, Theresa Pape, Alvaro Pascual-Leone, Kristin M. Pearson-Fuhrhop, P. Hunter Peckham, Tamara L. Pelleshi, Catherine Verrier Piersol, Thomas Platz, Marcus Pohl, Dejan B. Popović, Andrew M. Poulos, Maulik Purohit, Hui-Xin Qi, Debbie Rand, Mahendra S. Rao, Josef P. Rauschecker, Aimee Reiss, Carol L. Richards, Keith M. Robinson, Melvyn Roerdink, John C. Rosenbek, Serge Rossignol, Edward S. Ruthazer, Arash Sahraie, Krishnankutty Sathian, Marc H. Schieber, Brian J. Schmidt, Michael E. Selzer, Mijail D. Serruya, Himanshu Sharma, Michael Shifman, Jerry Silver, Thomas Sinkjær, George M. Smith, Young-Jin Son, Tim Spencer, John D. Steeves, Oswald Steward, Sheela Stuart, Austin J. Sumner, Chin Lik Tan, Robert W. Teasell, Gareth Thomas, Aiko K. Thompson, Richard F. Thompson, Wesley J. Thompson, Erika Timar, Ceri T. Trevethan, Christopher Trimby, Gary R. Turner, Mark H. Tuszynski, Erna A. van Niekerk, Ricardo Viana, Difei Wang, Anthony B. Ward, Nick S. Ward, Stephen G. Waxman, Patrice L. Weiss, Jörg Wissel, Steven L. Wolf, Jonathan R. Wolpaw, Sharon Wood-Dauphinee, Ross D. Zafonte, Binhai Zheng, Richard D. Zorowitz
- Edited by Michael Selzer, Stephanie Clarke, Leonardo Cohen, Gert Kwakkel, Robert Miller, Case Western Reserve University, Ohio
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- Book:
- Textbook of Neural Repair and Rehabilitation
- Published online:
- 05 May 2014
- Print publication:
- 24 April 2014, pp ix-xvi
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Contributor affiliations
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- By Frank Andrasik, Melissa R. Andrews, Ana Inés Ansaldo, Evangelos G. Antzoulatos, Lianhua Bai, Ellen Barrett, Linamara Battistella, Nicolas Bayle, Michael S. Beattie, Peter J. Beek, Serafin Beer, Heinrich Binder, Claire Bindschaedler, Sarah Blanton, Tasia Bobish, Michael L. Boninger, Joseph F. Bonner, Chadwick B. Boulay, Vanessa S. Boyce, Anna-Katharine Brem, Jacqueline C. Bresnahan, Floor E. Buma, Mary Bartlett Bunge, John H. Byrne, Jeffrey R. Capadona, Stefano F. Cappa, Diana D. Cardenas, Leeanne M. Carey, S. Thomas Carmichael, Glauco A. P. Caurin, Pablo Celnik, Kimberly M. Christian, Stephanie Clarke, Leonardo G. Cohen, Adriana B. Conforto, Rory A. Cooper, Rosemarie Cooper, Steven C. Cramer, Armin Curt, Mark D’Esposito, Matthew B. Dalva, Gavriel David, Brandon Delia, Wenbin Deng, Volker Dietz, Bruce H. Dobkin, Marco Domeniconi, Edith Durand, Tracey Vause Earland, Georg Ebersbach, Jonathan J. Evans, James W. Fawcett, Uri Feintuch, Toby A. Ferguson, Marie T. Filbin, Diasinou Fioravante, Itzhak Fischer, Agnes Floel, Herta Flor, Karim Fouad, Richard S. J. Frackowiak, Peter H. Gorman, Thomas W. Gould, Jean-Michel Gracies, Amparo Gutierrez, Kurt Haas, C.D. Hall, Hans-Peter Hartung, Zhigang He, Jordan Hecker, Susan J. Herdman, Seth Herman, Leigh R. Hochberg, Ahmet Höke, Fay B. Horak, Jared C. Horvath, Richard L. Huganir, Friedhelm C. Hummel, Beata Jarosiewicz, Frances E. Jensen, Michael Jöbges, Larry M. Jordan, Jon H. Kaas, Andres M. Kanner, Noomi Katz, Matthew S. Kayser, Annmarie Kelleher, Gerd Kempermann, Timothy E. Kennedy, Jürg Kesselring, Fary Khan, Rachel Kizony, Jeffery D. Kocsis, Boudewijn J. Kollen, Hubertus Köller, John W. Krakauer, Hermano I. Krebs, Gert Kwakkel, Bradley Lang, Catherine E. Lang, Helmar C. Lehmann, Angelo C. Lepore, Glenn S. Le Prell, Mindy F. Levin, Joel M. Levine, David A. Low, Marilyn MacKay-Lyons, Jeffrey D. Macklis, Margaret Mak, Francine Malouin, William C. Mann, Paul D. Marasco, Christopher J. Mathias, Laura McClure, Jan Mehrholz, Lorne M. Mendell, Robert H. Miller, Carol Milligan, Beth Mineo, Simon W. Moore, Jennifer Morgan, Charbel E-H. Moussa, Martin Munz, Randolph J. Nudo, Joseph J. Pancrazio, Theresa Pape, Alvaro Pascual-Leone, Kristin M. Pearson-Fuhrhop, P. Hunter Peckham, Tamara L. Pelleshi, Catherine Verrier Piersol, Thomas Platz, Marcus Pohl, Dejan B. Popović, Andrew M. Poulos, Maulik Purohit, Hui-Xin Qi, Debbie Rand, Mahendra S. Rao, Josef P. Rauschecker, Aimee Reiss, Carol L. Richards, Keith M. Robinson, Melvyn Roerdink, John C. Rosenbek, Serge Rossignol, Edward S. Ruthazer, Arash Sahraie, Krishnankutty Sathian, Marc H. Schieber, Brian J. Schmidt, Michael E. Selzer, Mijail D. Serruya, Himanshu Sharma, Michael Shifman, Jerry Silver, Thomas Sinkjær, George M. Smith, Young-Jin Son, Tim Spencer, John D. Steeves, Oswald Steward, Sheela Stuart, Austin J. Sumner, Chin Lik Tan, Robert W. Teasell, Gareth Thomas, Aiko K. Thompson, Richard F. Thompson, Wesley J. Thompson, Erika Timar, Ceri T. Trevethan, Christopher Trimby, Gary R. Turner, Mark H. Tuszynski, Erna A. van Niekerk, Ricardo Viana, Difei Wang, Anthony B. Ward, Nick S. Ward, Stephen G. Waxman, Patrice L. Weiss, Jörg Wissel, Steven L. Wolf, Jonathan R. Wolpaw, Sharon Wood-Dauphinee, Ross D. Zafonte, Binhai Zheng, Richard D. Zorowitz
- Edited by Michael E. Selzer, Stephanie Clarke, Leonardo G. Cohen, Gert Kwakkel, Robert H. Miller, Case Western Reserve University, Ohio
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- Book:
- Textbook of Neural Repair and Rehabilitation
- Published online:
- 05 June 2014
- Print publication:
- 24 April 2014, pp ix-xvi
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Science with the Murchison Widefield Array
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- Judd D. Bowman, Iver Cairns, David L. Kaplan, Tara Murphy, Divya Oberoi, Lister Staveley-Smith, Wayne Arcus, David G. Barnes, Gianni Bernardi, Frank H. Briggs, Shea Brown, John D. Bunton, Adam J. Burgasser, Roger J. Cappallo, Shami Chatterjee, Brian E. Corey, Anthea Coster, Avinash Deshpande, Ludi deSouza, David Emrich, Philip Erickson, Robert F. Goeke, B. M. Gaensler, Lincoln J. Greenhill, Lisa Harvey-Smith, Bryna J. Hazelton, David Herne, Jacqueline N. Hewitt, Melanie Johnston-Hollitt, Justin C. Kasper, Barton B. Kincaid, Ronald Koenig, Eric Kratzenberg, Colin J. Lonsdale, Mervyn J. Lynch, Lynn D. Matthews, S. Russell McWhirter, Daniel A. Mitchell, Miguel F. Morales, Edward H. Morgan, Stephen M. Ord, Joseph Pathikulangara, Thiagaraj Prabu, Ronald A. Remillard, Timothy Robishaw, Alan E. E. Rogers, Anish A. Roshi, Joseph E. Salah, Robert J. Sault, N. Udaya Shankar, K. S. Srivani, Jamie B. Stevens, Ravi Subrahmanyan, Steven J. Tingay, Randall B. Wayth, Mark Waterson, Rachel L. Webster, Alan R. Whitney, Andrew J. Williams, Christopher L. Williams, J. Stuart B. Wyithe
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 30 / 2013
- Published online by Cambridge University Press:
- 16 April 2013, e031
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Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
The Collfryn Hillslope Enclosure, Llansantffraid Deuddwr, Powys: Excavations 1980–1982
- William Britnell, Jenny Britnell, Timothy C. Darvill, Stephen Greep, Elizabeth Healey, Hilary Howard, Gillian Jones, Glynis Jones, Helen C. M. Keeley, Annie Milles, Graham C. Morgan, Elaine L. Morris, Mansel G. Spratling, Janet Webster, Peter V. Webster
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- Journal:
- Proceedings of the Prehistoric Society / Volume 55 / Issue 1 / 1989
- Published online by Cambridge University Press:
- 12 June 2014, pp. 89-134
- Print publication:
- 1989
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The report on partial rescue excavations of the Collfryn enclosure between 1980–82 presents a summary of the first large-scale investigation of one of the numerous semi-defensive cropmark and earthwork enclosure sites in the upper Severn valley in mid-Wales. Earlier prehistoric activity of an ephemeral nature is represented by a scattering of Mesolithic and Late Neolithic or early Bronze Age flintwork, and by a pit containing sherds of several different Beaker vessels. The first enclosed settlement, constructed in about the 3rd century bc probably consisted of three widely-spaced concentric ditches, associated with banks of simple dump construction, having a single gated entranceway on the downhill side. It covered an area of about 2.5 ha and appears to have been of a relatively high social status, and appropriate in size for a single extended-family group. This was subsequently reduced in about the 1st century bc to a double-ditched enclosure, by the recutting of the original inner ditch and the cutting of a new ditch immediately outside it. The habitation area between the 3rd and 1st centuries bc probably focused on timber buildings in the central enclosure of about 0.4 ha, whose gradually evolving pattern appears to have comprised between 3–4 roundhouses and 4–5 four-posters at any one time. Little excavation was undertaken between the outer ditches of the first phase settlement, but these are assumed to have been used as stock enclosures. A mixed farming economy is suggested by cattle, sheep/goat and pig remains, and remains of glume wheats, barley and oats. Industries included small-scale iron and bronze-working. The Iron Age settlement was essentially aceramic, although there are significant quantities of a coarse, oxidized ceramic probably representing salt traded from production centres in the Cheshire Plain. The entranceway was remodelled in about the late 1st or early 2nd, century AD by means of a timber-lined passage linked to a new gate on the line of the inner bank. There is equivocal evidence of continued occupation within the inner enclosure continuing until at least the mid-4th century AD, possibly at a comparatively low social level, associated with domestic structures of uncertain form sited on earlier roundhouse platforms, and including some four-posters and possible six-posters. Drainage ditches were dug across parts of the site during the Medieval and post-Medieval periods, which were associated with various structures, including a corn-drying kiln inserted into the inner enclosure bank in the 15th century.