51 results
Retrogressive failure of a static granular layer on an inclined plane
- A. S. Russell, C. G. Johnson, A. N. Edwards, S. Viroulet, F. M. Rocha, J. M. N. T. Gray
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- Journal:
- Journal of Fluid Mechanics / Volume 869 / 25 June 2019
- Published online by Cambridge University Press:
- 26 April 2019, pp. 313-340
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When a layer of static grains on a sufficiently steep slope is disturbed, an upslope-propagating erosion wave, or retrogressive failure, may form that separates the initially static material from a downslope region of flowing grains. This paper shows that a relatively simple depth-averaged avalanche model with frictional hysteresis is sufficient to capture a planar retrogressive failure that is independent of the cross-slope coordinate. The hysteresis is modelled with a non-monotonic effective basal friction law that has static, intermediate (velocity decreasing) and dynamic (velocity increasing) regimes. Both experiments and time-dependent numerical simulations show that steadily travelling retrogressive waves rapidly form in this system and a travelling wave ansatz is therefore used to derive a one-dimensional depth-averaged exact solution. The speed of the wave is determined by a critical point in the ordinary differential equation for the thickness. The critical point lies in the intermediate frictional regime, at the point where the friction exactly balances the downslope component of gravity. The retrogressive wave is therefore a sensitive test of the functional form of the friction law in this regime, where steady uniform flows are unstable and so cannot be used to determine the friction law directly. Upper and lower bounds for the existence of retrogressive waves in terms of the initial layer depth and the slope inclination are found and shown to be in good agreement with the experimentally determined phase diagram. For the friction law proposed by Edwards et al. (J. Fluid. Mech., vol. 823, 2017, pp. 278–315, J. Fluid. Mech., 2019, (submitted)) the magnitude of the wave speed is slightly under-predicted, but, for a given initial layer thickness, the exact solution accurately predicts an increase in the wave speed with higher inclinations. The model also captures the finite wave speed at the onset of retrogressive failure observed in experiments.
Effects of organic complexed or inorganic Co, Cu, Mn and Zn supplementation during a 45-day preconditioning period on productive and health responses of feeder cattle
- K. D. Lippolis, R. F. Cooke, L. G. T. Silva, K. M. Schubach, A. P. Brandao, R. S. Marques, C. K. Larson, J. R. Russell, S. A. Arispe, T. DelCurto, D. W. Bohnert
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This experiment evaluated production and health parameters among cattle offered concentrates containing inorganic or organic complexed sources of supplemental Cu, Co, Mn and Zn during a 45-day preconditioning period. In total, 90 Angus×Hereford calves were weaned at 7 months (day −1), sorted by sex, weaning BW and age (261±2 kg; 224±2 days), and allocated to 18 drylot pens (one heifer and four steers per pen) on day 0; thus, all pens had equivalent initial BW and age. Pens were randomly assigned to receive a corn-based preconditioning concentrate containing: (1) Cu, Co, Mn and Zn sulfate sources (INR), (2) Cu, Mn, Co and Zn complexed organic source (AAC) or (3) no Cu, Co, Mn and Zn supplementation (CON). From day 0 to 45, cattle received concentrate treatments (2.7 kg/animal daily, as-fed basis) and had free-choice access to orchardgrass (Dactylis glomerata L.), long-stem hay and water. The INR and AAC treatments were formulated to provide the same daily amount of Co, Cu, Mn and Zn at a 50-, 16-, 8- and ninefold increase, respectively, compared with the CON treatment. On day 46, cattle were transported to a commercial feedlot, maintained as a single pen, and offered a free-choice receiving diet until day 103. Calf full BW was recorded on days −1 and 0, 45 and 46, and 102 and 103 for average daily gain (ADG) calculation. Liver biopsy was performed on days 0 (used as covariate), 22 and 45. Cattle were vaccinated against respiratory pathogens on days 15, 29 and 46. Blood samples were collected on days 15, 29, 45, 47, 49, 53 and 60. During preconditioning, mean liver concentrations of Co, Zn and Cu were greater (P⩽0.03) in AAC and INR compared with CON. No treatment effects were detected (P⩾0.17) for preconditioning feed intake, ADG or feed efficiency. No treatment effects were detected (P⩾0.48) for plasma concentrations of antibodies against Mannheimia haemolytica, bovine viral diarrhea types 1 and 2 viruses. Plasma haptoglobin concentrations were similar among treatments (P=0.98). Mean plasma cortisol concentration was greater (P⩽0.04) in CON compared with INR and AAC. No treatment effects were detected (P⩾0.37) for cattle ADG during feedlot receiving. Hence, INR and AAC increased liver concentrations of Co, Zn and Cu through preconditioning, but did not impact cattle performance and immunity responses during preconditioning and feedlot receiving.
The wind-wind collision hole in eta Car
- A. Damineli, M. Teodoro, N. D. Richardson, T. R. Gull, M. F. Corcoran, K. Hamaguchi, J. H. Groh, G. Weigelt, D. J. Hillier, C. Russell, A. Moffat, K. R. Pollard, T. I. Madura
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- Journal:
- Proceedings of the International Astronomical Union / Volume 12 / Issue S329 / November 2016
- Published online by Cambridge University Press:
- 28 July 2017, pp. 186-190
- Print publication:
- November 2016
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Eta Carinae is one of the most massive observable binaries. Yet determination of its orbital and physical parameters is hampered by obscuring winds. However the effects of the strong, colliding winds changes with phase due to the high orbital eccentricity. We wanted to improve measures of the orbital parameters and to determine the mechanisms that produce the relatively brief, phase-locked minimum as detected throughout the electromagnetic spectrum. We conducted intense monitoring of the He ii λ4686 line in η Carinae for 10 months in the year 2014, gathering ~300 high S/N spectra with ground- and space-based telescopes. We also used published spectra at the FOS4 SE polar region of the Homunculus, which views the minimum from a different direction. We used a model in which the He ii λ4686 emission is produced by two mechanisms: a) one linked to the intensity of the wind-wind collision which occurs along the whole orbit and is proportional to the inverse square of the separation between the companion stars; and b) the other produced by the ‘bore hole’ effect which occurs at phases across the periastron passage. The opacity (computed from 3D SPH simulations) as convolved with the emission reproduces the behavior of equivalent widths both for direct and reflected light. Our main results are: a) a demonstration that the He ii λ4686 light curve is exquisitely repeatable from cycle to cycle, contrary to previous claims for large changes; b) an accurate determination of the longitude of periastron, indicating that the secondary star is ‘behind’ the primary at periastron, a dispute extended over the past decade; c) a determination of the time of periastron passage, at ~4 days after the onset of the deep light curve minimum; and d) show that the minimum is simultaneous for observers at different lines of sight, indicating that it is not caused by an eclipse of the secondary star, but rather by the immersion of the wind-wind collision interior to the inner wind of the primary.
Space Weather Storm Responses at Mars: Lessons from A Weakly Magnetized Terrestrial Planet
- J. G. Luhmann, C. F. Dong, Y. J. Ma, S. M. Curry, Yan Li, C. O. Lee, T. Hara, R. Lillis, J. Halekas, J. E. Connerney, J. Espley, D. A. Brain, Y. Dong, B. M. Jakosky, E. Thiemann, F. Eparvier, F. Leblanc, P. Withers, C. T. Russell
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- Journal:
- Proceedings of the International Astronomical Union / Volume 12 / Issue S328 / October 2016
- Published online by Cambridge University Press:
- 12 September 2017, pp. 211-217
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- October 2016
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Much can be learned from terrestrial planets that appear to have had the potential to be habitable, but failed to realize that potential. Mars shows evidence of a once hospitable surface environment. The reasons for its current state, and in particular its thin atmosphere and dry surface, are of great interest for what they can tell us about habitable zone planet outcomes. A main goal of the MAVEN mission is to observe Mars’ atmosphere responses to solar and space weather influences, and in particular atmosphere escape related to space weather ‘storms’ caused by interplanetary coronal mass ejections (ICMEs). Numerical experiments with a data-validated MHD model suggest how the effects of an observed moderately strong ICME compare to what happens during a more extreme event. The results suggest the kinds of solar and space weather conditions that can have evolutionary importance at a planet like Mars.
Study into the polyphenol content and antioxidant activity of rapeseed pomace extracts
- F. Pohl, M. Goua, G. Bermano, W. R. Russell, P. Maciel, P. Kong Thoo Lin
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- Journal:
- Proceedings of the Nutrition Society / Volume 75 / Issue OCE2 / 2016
- Published online by Cambridge University Press:
- 20 June 2016, E59
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The Parkes-MIT-NRAO Southern Sky Survey at 4850 MHz
- M. Griffith, A. E. Wright, A. J. Hunt, E. Troup, R. D. Ekers, P. Buckett, D. J. Cooke, G. Freeman, J. Glowacki, D. Jennings, U. Knop, B. Lam, I. McGovern, D. McConnell, R. P. Norris, R. Otrupcek, R. Twardy, T. Williams, G. Behrens, C. Chestnut, B. F. Burke, A. Fletcher, K. S. Russell, A. Savage, J. Lim, A. E. Vaughan, S. Côté, M. Anderson, A. Hons, G. L. White, S. Amy, A. Burgess, S. Chan, L. Cram, A. Gray, W. Walsh, D. Campbell-Wilson, V. McIntyre, P. Randall, M. Suters, W. J. Zealey
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- Publications of the Astronomical Society of Australia / Volume 9 / Issue 2 / 1991
- Published online by Cambridge University Press:
- 25 April 2016, pp. 243-245
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During 1990 we surveyed the southern sky using a multi-beam receiver at frequencies of 4850 and 843 MHz. The half-power beamwidths were 4 and 25 arcmin respectively. The finished surveys cover the declination range between +10 and −90 degrees declination, essentially complete in right ascension, an area of 7.30 steradians. Preliminary analysis of the 4850 MHz data indicates that we will achieve a five sigma flux density limit of about 30 mJy. We estimate that we will find between 80 000 and 90 000 new sources above this limit. This is a revised version of the paper presented at the Regional Meeting by the first four authors; the surveys now have been completed.
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
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- 27 April 2015, pp ix-xxx
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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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- Attention-Deficit Hyperactivity Disorder in Adults and Children
- Published online:
- 05 February 2015
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- 08 January 2015, pp vii-x
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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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- 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.
Contributors
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- By Krista Adamek, Ana Luisa K. Albernaz, J. Marcio Ayres†, Andrew J. Baker, Karen L. Bales, Adrian A. Barnett, Christopher Barton, John M. Bates, Jennie Becker, Bruna M. Bezerra, Júlio César Bicca-Marques, Richard Bodmer, Jean P. Boubli, Mark Bowler, Sarah A. Boyle, Christini Barbosa Caselli, Janice Chism, Elena P. Cunningham, José Maria C. da Silva, Lesa C. Davies, Nayara de Alcântara Cardoso, Manuella A. de Souza, Stella de la Torre, Ana Gabriela de Luna, Thomas R. Defler, Anthony Di Fiore, Eduardo Fernandez-Duque, Stephen F. Ferrari, Wilsea M.B. Figueiredo-Ready, Tracy Frampton, Paul A. Garber, Brian W. Grafton, L. Tremaine Gregory, Maria L. Harada, Amy Harrison-Levine, Walter C. Hartwig, Stefanie Heiduck, Eckhard W. Heymann, André Hirsch, Leandro Jerusalinsky, Gareth Jones, Richard F. Kay, Martin M. Kowalewski, Shawn M. Lehman, Laura Marsh, Jesús Martinez, William A. Mason, Hope Matthews, Wynlyn McBride, Shona McCann-Wood, W. Scott McGraw, D. Jeffrey Meldrum, Sally P. Mendoza, Nohelia Mercado, Russell A. Mittermeier, Mirjam N. Nadjafzadeh, Marilyn A. Norconk, Robert Gary Norman, Marcela Oliveira, Marcelo M. Oliveira, Maria Juliana Ospina Rodríguez, Erwin Palacios, Suzanne Palminteri, Liliam P. Pinto, Marcio Port-Carvalho, Leila Porter, Carlos Portillo-Quintero, George Powell, Ghillean T. Prance, Rodrigo C. Printes, Pablo Puertas, P. Kirsten Pullen, Helder L. Queiroz, Luis Reginaldo R. Rodrigues, Adriana Rodríguez, Alfred L. Rosenberger, Anthony B. Rylands, Ricardo R. Santos, Horacio Schneider, Eleonore Z.F. Setz, Suleima S.B. Silva, José S. Silva Júnior, Andrew T. Smith, Marcelo C. Sousa, Antonio S. Souto, Wilson R. Spironello, Masanaru Takai, Marcelo F. Tejedor, Cynthia L. Thompson, Diego G. Tirira, Raul Tupayachi, Bernardo Urbani, Liza M. Veiga, Marianela Velilla, João Valsecchi, Jean-Christophe Vié, Tatiana M. Vieira, Suzanne E. Walker-Pacheco, Rob Wallace, Patricia C. Wright, Charles E. Zartman
- Edited by Liza M. Veiga, Universidade Federal do Pará, Brazil, Adrian A. Barnett, Roehampton University, London, Stephen F. Ferrari, Universidade Federal de Sergipe, Brazil, Marilyn A. Norconk, Kent State University, Ohio
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- Evolutionary Biology and Conservation of Titis, Sakis and Uacaris
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- 05 April 2013
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- 11 April 2013, pp xii-xv
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Base Band Data for Testing Interference Mitigation Algorithms
- Jon F. Bell, Peter J. Hall, Warwick E. Wilson, Robert J. Sault, Rick J. Smegal, Malcolm R. Smith, Willem van Straten, Michael J. Kesteven, Richard H. Ferris, Frank H. Briggs, Graham J. Carrad, Malcom W. Sinclair, Russell G. Gough, John M. Sarkissian, John D. Bunton, Matthew Bailes
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 18 / Issue 1 / 2001
- Published online by Cambridge University Press:
- 05 March 2013, pp. 105-113
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Digital signal processing is one of many valuable tools for suppressing unwanted signals or inter-ference. Building hardware processing engines seems to be the way to best implement some classes of interference suppression but is, unfortunately, expensive and time-consuming, especially if several miti-gation techniques need to be compared. Simulations can be useful, but are not a substitute for real data. CSIRO’s Australia Telescope National Facility has recently commenced a ‘software radio telescope’ project designed to fill the gap between dedicated hardware processors and pure simulation. In this approach, real telescope data are recorded coherently, then processed offline. This paper summarises the current contents of a freely available database of base band recorded data that can be used to experiment with signal processing solutions. It includes data from the following systems: single dish, multi-feed receiver; single dish with reference antenna; and an array of six 22 m antennas with and without a reference antenna. Astronomical sources such as OH masers, pulsars and continuum sources subject to interfering signals were recorded. The interfering signals include signals from the US Global Positioning System (GPS) and its Russian equivalent (GLONASS), television, microwave links, a low-Earth-orbit satellite, various other transmitters, and signals leaking from local telescope systems with fast clocks. The data are available on compact disk, allowing use in general purpose computers or as input to laboratory hardware prototypes.
Contributors
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- By J. Todd Arnedt, Nazem Atassi, Judith Bebchuk, Devin L. Brown, Rickey E. Carter, Rick Chappell, William R. Clarke, Christopher S. Coffey, Peter G. Como, Merit Cudkowicz, Jeffrey Cummings, Gary R. Cutter, Gerald J. Dal Pan, E. Ray Dorsey, Susan S. Ellenberg, Jordan Elm, Changyong Feng, Elizabeth Fisher, Jacqueline A. French, Jean-Michel Germain, Joshua D. Grill, Robert G. Holloway, Karen C. Johnston, S. Claiborne Johnston, Cornelia L. Kamp, Russell Katz, Kathryn M. Kellogg, Karl Kieburtz, Scott Y. H. Kim, Jonathan Kimmelman, Bruce Levin, Michael P. McDermott, Eric A. Mann, John Markman, D. Troy Morgan, Gilmore N. O’Neill, Yuko Y. Palesch, John R. Pollard, R. Michael Poole, Mary E. Putt, Bemard Ravina, Richard A. Rudick, David Schoenfeld, Andrew D. Siderowf, Janet Wittes, Robert F. Woolson, Michael E. Yurcheshen
- Edited by Bernard Ravina, Jeffrey Cummings, Michael McDermott, R. Michael Poole
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- Book:
- Clinical Trials in Neurology
- Published online:
- 05 May 2012
- Print publication:
- 12 April 2012, pp ix-xii
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Behavioural changes after treatment with testosterone: case report
- P. J. V. Beumont, J. H. J. Bancroft, C. J. Beardwood, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 2 / Issue 1 / February 1972
- Published online by Cambridge University Press:
- 09 July 2009, pp. 70-72
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A male patient is described whose loss of sexual interest and activity was due to gonadal failure, presumably the result partly of Klinefelter's syndrome and partly of orchitis, though the latter was unilateral. He showed no change during a placebo control period, but within a few days of starting replacement treatment with testosterone he reported a return of sexual interest and showed a response to sexually arousing stimuli; sexual attitudes also improved. This case is of interest because of the specific and rapid psychological response to the correction of an androgen deficiency.
Developmental dyscalculia: a brief report on four cases
- P. D. Slade, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 1 / Issue 4 / August 1971
- Published online by Cambridge University Press:
- 09 July 2009, pp. 292-298
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Four patients with ‘developmental dyscalculia’ are described who were initially identified on the basis of clinical tests, reports of longstanding and severe difficulties in arithmetic, and psychological test results. Descriptive psychological testing indicated (1) that the arithmetical deficits could not be accounted for on the basis of a generally low level of intellectual functioning; (2) that of the four basic arithmetical processes that of multiplication was relatively more deficient; (3) that this relative deficiency in multiplication stemmed from a faulty grasp of basic multiplication tables; that this was a real difficulty, experienced subjectively by the patient, and one that could not be accounted for simply by carelessness; and finally, that the degree of difficulty experienced varied with the multiplication table involved. Two kinds of attempt were made to improve arithmetical functioning. The first involved brief remedial coaching programmes directed at the basic multiplication tables: relatively little success was obtained with this method. The second kind of attempt involved methods of bypassing the necessity for learning multiplication tables: some success was obtained with these methods. The discussion concentrates on some of the features which may provide possibly useful cues for identifying ‘developmental dyscalculia’: these are classified in terms of: (1) pattern of deficit displayed; (2) qualitative features of arithmetical performance; and (3) response to remedial teaching. Some suggestions are made concerning further lines of investigation.
Value of family background and clinical features as predictors of long-term outcome in anorexia nervosa: four-year follow-up study of 41 patients
- H. G. Morgan, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 5 / Issue 4 / November 1975
- Published online by Cambridge University Press:
- 09 July 2009, pp. 355-371
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This is a prognostic study on 41 patients with anorexia nervosa (including three males) who satisfied defined diagnostic criteria. The patients had all been admitted to a metabolic unit where the mainstay of treatment was nursing care aimed at rapid restoration of body weight. A follow-up was conducted after a minimum lapse of four years after each patient's discharge from hospital. The outcome of the patient's illness was expressed in terms of an ‘average outcome score’ and a ‘general outcome’. The series included a relatively high proportion of patients with a long illness who had received previous psychiatric treatment. Their families tended to come from higher social classes; a disturbed relationship with the patient was frequent. Premorbid disturbances in personality development were also common. The immediate response to treatment was excellent, with the majority of the patients returning to a normal weight, but relapses after discharge were common and readmissions were necessary in half the patients. At follow-up, the patients fell into the following defined categories: ‘good’ (39%), ‘intermediate’ (27%), ‘poor’ (29%), died (5%). Most of the patients who failed to recover continued to display the clinical features characteristic of anorexia nervosa. Among predictors of an unfavourable outcome were found a relatively late age of onset, a longer duration of illness, previous admissions to psychiatric hospitals, a disturbed relationship between the patient and other members of the family, and premorbid personality difficulties. It is suggested that the long-term outcome found in a series will depend more on factors influencing patient referral according to the severity of their illness, rather than on the method of treatment itself. The illness may last several years before eventual improvement or recovery, and a follow-up study must be extended over at least four years to be meaningful. An accurate prediction of eventual outcome is almost impossible, but late recoveries justify an optimistic outlook and continued therapeutic endeavour.
Disturbances in the regulation of body temperature in anorexia nervosa
- A. Wakeling, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 1 / Issue 1 / November 1970
- Published online by Cambridge University Press:
- 09 July 2009, pp. 30-39
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The regulation of body temperature was investigated in 11 patients with anorexia nervosa, initially while they were in a malnourished state and again after refeeding when they had reached a near normal weight. The results suggest that there may be a primary defect of temperature regulation in anorexia nervosa which is linked in some way with the feeding disorder characteristic of this illness.
Awareness of body dimensions in anorexia nervosa: cross-sectional and longitudinal studies
- P. D. Slade, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 3 / Issue 2 / May 1973
- Published online by Cambridge University Press:
- 09 July 2009, pp. 188-199
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Patients suffering from anorexia nervosa usually exhibit extreme concern over their physical size and weight. This tendency, noted by many observers, has been variously interpreted. However, few experimental studies of this phenomenon have been reported. In the present paper an objective technique for determining bodily perception is described, together with a series of studies involving investigation of bodily perception in anorexia nervosa. In the first study a group of anorexia nervosa patients was compared with a group of normal female controls, results showing that, unlike the controls, the patients exhibited marked overestimation of the width of their own body. Moreover, this tendency was found not to extend to perception of physical objects. The results of a second study showed that the overestimation of body width was less marked when the patients were required to gauge the size of a female model. In addition, they were found to be remarkably accurate in assessing physical height, both of themselves and of the model. A third study explored the effects of refeeding on the patients' tendency to see themselves as abnormally wide (and fat). The findings showed that this tendency decreased as patients put on weight. Moreover, the degree of overestimation of body width exhibited by patients was found to bear a relationship to their progress after discharge from hospital: when this persisted after weight gain, a subsequent relapse was more likely.
The occurrence of the syndrome of anorexia nervosa in male subjects
- P. J. V. Beumont, C. J. Beardwood, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 2 / Issue 3 / August 1972
- Published online by Cambridge University Press:
- 09 July 2009, pp. 216-231
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A syndrome characterized by the psychopathological features of anorexia nervosa occurs in male subjects. There have been 25 cases previously reported in the literature which appear to be fairly typical of the condition and the present paper adds the case histories of another six patients. Endocrine investigation on these patients reveals a disorder of urinary excretion levels of testosterone and of total gonadotrophic activity, which is comparable to the disturbance of sex hormones that accompanies the menstrual disturbance of female patients with anorexia nervosa. The exact nature of the endocrine disturbance in the male, however, is still less well understood than that in the female.
Serotonin activity in anorexia nervosa after long-term weight restoration: response to D-fenfluramine challenge
- A-M. O'Dwyer, J. V. Lucey, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 26 / Issue 2 / March 1996
- Published online by Cambridge University Press:
- 09 July 2009, pp. 353-359
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Abnormalities in central serotonin function have been implicated in the pathogenesis of anorexia nervosa. It is difficult, however, to separate neuroendocrine abnormalities induced by weight loss and malnutrition from those related primarily to the disorder itself. To minimize these influences, this study assessed long-term weight restored anorexics. A correlation between persistent eating-related psychopathology, co-morbid illness and serotonin dysfunction was sought. Nine female weight-restored out-patients who had previously fulfilled DSM-III-R criteria for anorexia nervosa and nine healthy controls participated. Following baseline estimation, prolactin and cortisol responses to 30 mg p.o. of D-fenfluramine were measured over a 5 h period. Eating related psychopathology was assessed using the Eating Disorders Inventory and Eating Attitudes Test. Depressive and obsessional symptoms were measured using the Beck Depressive and Maudsley Obsessive–Compulsive Inventories respectively. The Tridimensional Personality Questionnaire assessed impulsivity. The weight-restored anorexic group exhibited persistent eating-related psychopathology and significant co-morbid symptomatology. There was no difference between long-term weight restored anorexics and controls in their endocrine response to D-fenfluramine. Long-term weight-recovered anorexic subjects continued to exhibit behavioural and attitudinal disturbances characteristic of anorexia nervosa. The results suggest that abnormalities in 5HT activity do not contribute significantly to trait status in anorexia nervosa.
The effects of clomiphene citrate on the hypothalamic–pituitary–gonadal axis in anorexia nervosa
- A. Wakeling, J. C. Marshall, C. J. Beardwood, V. F. A. de Souza, G. F. M. Russell
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- Journal:
- Psychological Medicine / Volume 6 / Issue 3 / August 1976
- Published online by Cambridge University Press:
- 09 July 2009, pp. 371-380
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Serum luteinizing hormone(LH) responses to a course of clomiphene citrate were studied in eleven patients with anorexia nervosa at different stages of the illness. In malnourished patients basal levels of LH were invariably low. With the resumption of a normal weight a small but definite rise in LH levels was observed but this spontaneous response to weight gain was variable in that many patients continued to exhibit abnormally low LH levels.
The response to clomiphene in terms of a rise in basal LH levels after administration of the drug, followed by a second peak of LH and subsequent menstrual bleeding, was clearly dependent in part on the patient's nutritional state. In the malnourished state the response to clomiphene was usually either absent or incomplete. After the resumption of a more normal weight, the patients invariably showed an initial rise in LH after the clomiphene, but the second LH peak and subsequent menstruation were frequently not demonstrated. Six patients maintained a normal body weight for at least six months after a course of clomiphene, but only three of them resumed cyclical menstrual bleeding. It was concluded that factors additional to the nutritional state contribute to the prolonged amenorrhoea in anorexia nervosa and that clomiphene appears to have only a limited role in the treatment and management of patients with the disorder. Some aspects of current knowledge of the endocrine mechanisms that regulate normal menstruation and of the mode of action of clomiphene are outlined.
The results of the present study are discussed against this background in an attempt to elucidate further the hypothalamic disorder underlying the amenorrhoea in anorexia nervosa.