27 results
Early technology review: towards an expedited pathway
- Leslie Levin, Murray Sheldon, Robert S. McDonough, Naomi Aronson, Maroeska Rovers, C. Michael Gibson, Sean Robert Tunis, Richard E. Kuntz
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- Journal:
- International Journal of Technology Assessment in Health Care / Volume 40 / Issue 1 / 2024
- Published online by Cambridge University Press:
- 29 January 2024, e13
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Objectives
Evidence development for medical devices is often focused on satisfying regulatory requirements with the result that health professional and payer expectations may not be met, despite considerable investment in clinical trials. Early engagement with payers and health professionals could allow companies to understand these expectations and reflect them in clinical study design, increasing chances of positive coverage determination and adoption into clinical practice.
MethodsAn example of early engagement through the EXCITE International model using an early technology review (ETR) is described which includes engagement with payers and health professionals to better inform companies to develop data that meet their expectations. ETR is based on an early evidence review, a framework of expectations that guides the process and identified gaps in evidence. The first fourteen ETRs were reviewed for examples of advice to companies that provided additional information from payers and health professionals that was thought likely to impact on downstream outcomes or strategic direction. Given that limitations were imposed by confidentiality, examples were genericized.
ResultsAdvice through early engagement can inform evidence development that coincides with expectations of payers and health professionals through a structured, objective, evidence-based approach. This could reduce the risk of business-related adverse outcomes such as failure to secure a positive coverage determination and/or acceptance by expert health professionals.
ConclusionsEarly engagement with key stakeholders exemplified by the ETR approach offers an alternative to the current approach of focusing on regulatory expectations. This could reduce the time to reimbursement and clinical adoption and benefit patient outcomes and/or health system efficiencies.
Dexmedetomidine Orally Dissolving Film for Acute Agitation Associated with Schizophrenia or Bipolar Disorder: SERENITY I and SERENITY II Trials
- Leslie L. Citrome, Sheldon H. Preskorn, Lavanya Rajachandran, Robert Risinger
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- Journal:
- CNS Spectrums / Volume 27 / Issue 2 / April 2022
- Published online by Cambridge University Press:
- 28 April 2022, p. 242
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Episodes of acute agitation associated with psychiatric disorders are often managed in emergency and inpatient settings. These trials evaluated the efficacy, safety, and tolerability of dexmedetomidine orally dissolving film (ODF), an investigational treatment for acute agitation associated with schizophrenia (SERENITY I) or bipolar disorder (SERENITY II). Dexmedetomidine ODF is a highly selective agonist of alpha 2 adrenergic receptors that modulate norepinephrine release from the locus coeruleus. Two randomized, double-blind, placebo-controlled Phase 3 trials in 15 U.S. sites included participants aged 18 to 75 with acute agitation and a DSM-5 diagnosis of schizophrenia or schizoaffective disorder (Serenity I) or bipolar disorder I or II (Serenity II). Agitation was defined as ³14 on the Positive and Negative Syndrome Scale-Excited Component (PEC) at screening and baseline, and ³4 on at least 1 of the 5 PEC items (poor impulse control, tension, hostility, uncooperativeness, and excitement) at baseline. Randomization was 1:1:1 to dexmedetomidine ODF 120 or 180 mcg or matching placebo. All participants self-administered study drugs. For persistent or recurrent agitation after 2 hours, investigators could redose a half-dose. The primary endpoint was changed from baseline in PEC total at 2 hours. The secondary endpoint was the earliest time at which a statistically significant separation from placebo occurred.A total of 380 patients were randomized in each trial (N = 760). All doses of dexmedetomidine ODF met the primary endpoint of change from baseline in PEC at 2 hours vs placebo (P < .001). Statistically significant improvement in PEC occurred as early as 20 minutes with the 180 mcg dose in both trials. A second (half-strength) dose was given to 10 (4.0%) participants in the 180 mcg groups, 34 (13.3%) in the 120 mcg groups, and 58 (23.0%) in the placebo groups in Serenity 1 and Serenity 2. There were no drug-related serious or severe TEAEs in either trial. No participant was unarousable by the Agitation and Calmness Evaluation Scale. For dexmedetomidine 180 mcg, 120 mcg, and placebo, the incidence of TEAEs was 37.3%, 39.5%, and 15.1% in Serenity 1 and 35.7%, 34.9%, and 17.5% in Serenity 2. Somnolence was the most common TEAE in both trials (22% Serenity I; 21% Serenity 2). Of 110 somnolence reports, 75% were mild and 25% moderate. In 2 Phase 3 trials, the investigational treatment, dexmedetomidine ODF, effectively treated acute agitation associated with schizophrenia or bipolar disorder, with onset of action as early as 20 minutes at the 180 mcg dose. Both doses of dexmedetomidine ODF produced a calming effect without unarousable sedation. Mild or moderate somnolence was the most common AE. Dexmedetomidine ODF is a selective alpha-2 adrenergic receptor agonist that allows self-administration, making it a potential addition to noninvasive treatments for acute agitation associated with schizophrenia or bipolar disorder.
FundingBioXcel Therapeutics
PP34 A Cost-Utility Analysis Of The Syncope: Pacing Or Recording Trial
- Mark Hofmeister, Robert Sheldon, Eldon Spackman, Satish Raj, Mario Talajic, Giuliano Becker, Vidal Essebag, M. Sarah Rose, Deborah Ritchie, Carlos Morillo, Andrew Krahn, Shahana Safdar, Connor Maxey, Fiona Clement
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- Journal:
- International Journal of Technology Assessment in Health Care / Volume 34 / Issue S1 / 2018
- Published online by Cambridge University Press:
- 03 January 2019, pp. 78-79
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Introduction:
For patients with bifascicular block and syncope of unknown origin, different American Heart Association guidelines give Class 2A recommendations for two treatments: the implantable loop recorder (ILR) and empiric pacemaker insertion (PM). Equipoise reflected in guidelines may contribute to uncertainty in management and inefficient resource use. The objective of this analysis is to determine the cost-effectiveness of ILR compared to PM in the management of older adults (age>50 years) with bifascicular block and syncope over two years, from the perspective of a Canadian publicly funded health care system, in the Syncope: Pacing or Recording In ThE Later Years (SPRITELY) trial.
Methods:Resource utilization data was collected throughout the trial, and unit costs were assigned (2017 Canadian dollars). Utility was measured at baseline and annually with the EQ-5D-3L. Quality adjusted life years (QALYs) were calculated as area-under-the-curve, and adjusted for baseline imbalances in utility. Confidence intervals for the incremental cost effectiveness ratio were generated with non-parametric bootstrapping.
Results:Mean cost in participants randomized to PM was CAD 9,759 (USD 7,400), compared to CAD 13,453 (USD 10,200) in participants randomized to ILR. The ILR strategy resulted in 0.020 QALYs more than the PM strategy. The incremental cost effectiveness ratio was CAD 186,553 (95% CI: −831,950–1,191,816) (USD 141,900, 95% CI: −632,740–906,440) per additional QALY. In 1,000 bootstrapped replicates, the cost of the ILR strategy was always greater than that of the PM strategy. At the threshold of CAD 50,000 (USD 38,000) per additional QALY, the probability that the ILR strategy is the cost effective option is 0.504.
Conclusions:ILR costs were greater than PM costs, with little difference in QALY outcomes over two-years. Findings are generalizable to patients similar to SPRITELY participants, from the perspective of the Canadian health care system. However, practice pattern variation and payment systems inhibit generalizability to other countries. Future analysis will explore cost and QALY outcomes in countries that participated in the SPRITELY trial.
Preliminary assessment of the scope and scale of illegal killing and taking of birds in the Mediterranean
- ANNE-LAURE BROCHET, WILLEM VAN DEN BOSSCHE, SHARIF JBOUR, P. KARIUKI NDANG’ANG’A, VICTORIA R. JONES, WED ABDEL LATIF IBRAHIM ABDOU, ABDEL RAZZAQ AL- HMOUD, NABEGH GHAZAL ASSWAD, JUAN CARLOS ATIENZA, IMAD ATRASH, NICHOLAS BARBARA, KEITH BENSUSAN, TAULANT BINO, CLAUDIO CELADA, SIDI IMAD CHERKAOUI, JULIETA COSTA, BERNARD DECEUNINCK, KHALED SALEM ETAYEB, CLAUDIA FELTRUP-AZAFZAF, JERNEJ FIGELJ, MARCO GUSTIN, PRIMOŽ KMECL, VLADO KOCEVSKI, MALAMO KORBETI, DRAŽEN KOTROŠAN, JUAN MULA LAGUNA, MATTEO LATTUADA, DOMINGOS LEITÃO, PAULA LOPES, NICOLÁS LÓPEZ-JIMÉNEZ, VEDRAN LUCIĆ, THIERRY MICOL, AÏSSA MOALI, YOAV PERLMAN, NICOLA PILUDU, DANAE PORTOLOU, KSENIJA PUTILIN, GWENAEL QUAINTENNE, GHASSAN RAMADAN-JARADI, MILAN RUŽIĆ, ANNA SANDOR, NERMINA SARAJLI, DARKO SAVELJIĆ, ROBERT D. SHELDON, TASSOS SHIALIS, NIKOS TSIOPELAS, FRAN VARGAS, CLAIRE THOMPSON, ARIEL BRUNNER, RICHARD GRIMMETT, STUART H.M. BUTCHART
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- Bird Conservation International / Volume 26 / Issue 1 / March 2016
- Published online by Cambridge University Press:
- 03 March 2016, pp. 1-28
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Illegal killing/taking of birds is a growing concern across the Mediterranean. However, there are few quantitative data on the species and countries involved. We assessed numbers of individual birds of each species killed/taken illegally in each Mediterranean country per year, using a diverse range of data sources and incorporating expert knowledge. We estimated that 11–36 million individuals per year may be killed/taken illegally in the region, many of them on migration. In each of Cyprus, Egypt, Italy, Lebanon and Syria, more than two million birds may be killed/taken on average each year. For species such as Blackcap Sylvia atricapilla, Common Quail Coturnix coturnix, Eurasian Chaffinch Fringilla coelebs, House Sparrow Passer domesticus and Song Thrush Turdus philomelos, more than one million individuals of each species are estimated to be killed/taken illegally on average every year. Several species of global conservation concern are also reported to be killed/taken illegally in substantial numbers: Eurasian Curlew Numenius arquata, Ferruginous Duck Aythya nyroca and Rock Partridge Alectoris graeca. Birds in the Mediterranean are illegally killed/taken primarily for food, sport and for use as cage-birds or decoys. At the 20 worst locations with the highest reported numbers, 7.9 million individuals may be illegally killed/taken per year, representing 34% of the mean estimated annual regional total number of birds illegally killed/taken for all species combined. Our study highlighted the paucity of data on illegal killing/taking of birds. Monitoring schemes which use systematic sampling protocols are needed to generate increasingly robust data on trends in illegal killing/taking over time and help stakeholders prioritise conservation actions to address this international conservation problem. Large numbers of birds are also hunted legally in the region, but specific totals are generally unavailable. Such data, in combination with improved estimates for illegal killing/taking, are needed for robustly assessing the sustainability of exploitation of birds.
Neurocardiology. 1994. Edited by J.A. Armour and J.L. Ardell. Published by Oxford University PressCanada. 443 pages. $C91.00.
- Robert Sheldon
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- Canadian Journal of Neurological Sciences / Volume 22 / Issue 3 / August 1995
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- 18 September 2015, p. 251
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Hypoparathyroidism and Pseudotumor Cerebri: An Infrequent Clinical Association
- Robert S. Sheldon, Werner J. Becker, David A. Hanley, Ronald L. Culver
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- Canadian Journal of Neurological Sciences / Volume 14 / Issue 4 / November 1987
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- 18 September 2015, pp. 622-625
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We report a patient with chronic, untreated idiopathic hypoparathyroidism who presented with papilledema and progressive deterioration of visual function. The papilledema resolved with treatment of the hypocalcemia. Visual acuity progressively improved as the serum calcium rose during treatment with vitamin D and calcium supplements. Lumbar puncture may also have contributed to the normalization of cerebrospinal fluid pressure and recovery of vision in this patient. The association of hypoparathyroidism and pseudotumor cerebri is rare, and a retrospective review of 41 patients with hypoparathyroidism admitted to two local general hospitals revealed no other cases.
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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
- Print publication:
- 27 April 2015, pp ix-xxx
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- By Tom Abbott, Gareth L. Ackland, Hollman D. Aya, Berthold Bein, Karim Bendjelid, Matthieu Biais, Elizabeth J. Bridges, Maxime Cannesson, Cédric Carrié, Alice Carter, Maurizio Cecconi, Daniel Chappell, Jason H. Chua, Gary Colins, Diego Orbegozo Cortes, Lester A. H. Critchley, Daniel De Backer, Katia Donadello, Eric Edison, Byron D. Fergerson, Tong J. Gan, Michael T. Ganter, Leslie M. Garson, Christoph K. Hofer, Christoph Ilies, James M. Isbell, Matthias Jacob, Mazyar Javidroozi, Zeev N. Kain, Elisa Kam, Gautam Kumar, Yannick Le Manach, Sheldon Magder, Aman Mahajan, Gerard R. Manecke, Paul E. Marik, Joseph Meltzer, Debra R. Metter, Timothy E. Miller, Xavier Monnet, Michael Mythen, Rudolph Nguyen, Rupert Pearse, Michael R. Pinsky, Davinder Ramsingh, Steffen Rex, Andrew Rhodes, Joseph Rinehart, Mathieu Sèrié, Aryeh Shander, Nils Siegenthaler, Ann B. Singleton, Faraz Syed, Jean-Louis Teboul, Robert H. Thiele, Shermeen B. Vakharia, Trung Vu, Nathan H. Waldron, David Walker, William Wilson
- Edited by Maxime Cannesson, University of California, Irvine, Rupert Pearse
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- Perioperative Hemodynamic Monitoring and Goal Directed Therapy
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- 05 September 2014
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- 04 September 2014, pp vii-x
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- By Rene Almeling, John B. Appleby, Lucy Blake, Kate Bourne, Andrea Mechanick Braverman, Naomi Cahn, Lorraine Culley, Fatemeh Ebtehaj, Jeannette Edwards, Tabitha Freeman, Lucy Frith, Susan Golombok, Susanna Graham, Cathy Herbrand, Nicky Hudson, Susan Imrie, Vasanti Jadva, Sarah Jennings, Anja J. Karnein, Hallvard Lillehammer, Julie McCandless, Petra Nordqvist, Guido Pennings, Veerle Provoost, Martin Richards, Sally Sheldon, Carol Smart, Marcin Smietana, Venessa Smith, Helen Statham, Sophie Zadeh, Irenee Daly, Yolanda Garcia-Ruiz, Zeynep Gürtin, Robert Klitzman, Soraya Tremayne, Sheryl Vanderpoel, Effy Vayena, Katharine Wright
- Edited by Tabitha Freeman, University of Cambridge, Susanna Graham, University of Cambridge, Fatemeh Ebtehaj, University of Cambridge, Martin Richards, University of Cambridge
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- Relatedness in Assisted Reproduction
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- 05 August 2014
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- 14 August 2014, pp vii-ix
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- By Lenard A. Adler, Pinky Agarwal, Rehan Ahmed, Jagga Rao Alluri, Fawaz Al-Mufti, Samuel Alperin, Michael Amoashiy, Michael Andary, David J. Anschel, Padmaja Aradhya, Vandana Aspen, Esther Baldinger, Jee Bang, George D. Baquis, John J. Barry, Jason J. S. Barton, Julius Bazan, Amanda R. Bedford, Marlene Behrmann, Lourdes Bello-Espinosa, Ajay Berdia, Alan R. Berger, Mark Beyer, Don C. Bienfang, Kevin M. Biglan, Thomas M. Boes, Paul W. Brazis, Jonathan L. Brisman, Jeffrey A. Brown, Scott E. Brown, Ryan R. Byrne, Rina Caprarella, Casey A. Chamberlain, Wan-Tsu W. Chang, Grace M. Charles, Jasvinder Chawla, David Clark, Todd J. Cohen, Joe Colombo, Howard Crystal, Vladimir Dadashev, Sarita B. Dave, Jean Robert Desrouleaux, Richard L. Doty, Robert Duarte, Jeffrey S. Durmer, Christyn M. Edmundson, Eric R. Eggenberger, Steven Ender, Noam Epstein, Alberto J. Espay, Alan B. Ettinger, Niloofar (Nelly) Faghani, Amtul Farheen, Edward Firouztale, Rod Foroozan, Anne L. Foundas, David Elliot Friedman, Deborah I. Friedman, Steven J. Frucht, Oded Gerber, Tal Gilboa, Martin Gizzi, Teneille G. Gofton, Louis J. Goodrich, Malcolm H. Gottesman, Varda Gross-Tsur, Deepak Grover, David A. Gudis, John J. Halperin, Maxim D. Hammer, Andrew R. Harrison, L. Anne Hayman, Galen V. Henderson, Steven Herskovitz, Caitlin Hoffman, Laryssa A. Huryn, Andres M. Kanner, Gary P. Kaplan, Bashar Katirji, Kenneth R. Kaufman, Annie Killoran, Nina Kirz, Gad E. Klein, Danielle G. Koby, Christopher P. Kogut, W. Curt LaFrance, Patrick J.M. Lavin, Susan W. Law, James L. Levenson, Richard B. Lipton, Glenn Lopate, Daniel J. Luciano, Reema Maindiratta, Robert M. Mallery, Georgios Manousakis, Alan Mazurek, Luis J. Mejico, Dragana Micic, Ali Mokhtarzadeh, Walter J. Molofsky, Heather E. Moss, Mark L. Moster, Manpreet Multani, Siddhartha Nadkarni, George C. Newman, Rolla Nuoman, Paul A. Nyquist, Gaia Donata Oggioni, Odi Oguh, Denis Ostrovskiy, Kristina Y. Pao, Juwen Park, Anastas F. Pass, Victoria S. Pelak, Jeffrey Peterson, John Pile-Spellman, Misha L. Pless, Gregory M. Pontone, Aparna M. Prabhu, Michael T. Pulley, Philip Ragone, Prajwal Rajappa, Venkat Ramani, Sindhu Ramchandren, Ritesh A. Ramdhani, Ramses Ribot, Heidi D. Riney, Diana Rojas-Soto, Michael Ronthal, Daniel M. Rosenbaum, David B. Rosenfield, Durga Roy, Michael J. Ruckenstein, Max C. Rudansky, Eva Sahay, Friedhelm Sandbrink, Jade S. Schiffman, Angela Scicutella, Maroun T. Semaan, Robert C. Sergott, Aashit K. Shah, David M. Shaw, Amit M. Shelat, Claire A. Sheldon, Anant M. Shenoy, Yelizaveta Sher, Jessica A. Shields, Tanya Simuni, Rajpaul Singh, Eric E. Smouha, David Solomon, Mehri Songhorian, Steven A. Sparr, Egilius L. H. Spierings, Eve G. Spratt, Beth Stein, S.H. Subramony, Rosa Ana Tang, Cara Tannenbaum, Hakan Tekeli, Amanda J. Thompson, Michael J. Thorpy, Matthew J. Thurtell, Pedro J. Torrico, Ira M. Turner, Scott Uretsky, Ruth H. Walker, Deborah M. Weisbrot, Michael A. Williams, Jacques Winter, Randall J. Wright, Jay Elliot Yasen, Shicong Ye, G. Bryan Young, Huiying Yu, Ryan J. Zehnder
- Edited by Alan B. Ettinger, Albert Einstein College of Medicine, New York, Deborah M. Weisbrot, State University of New York, Stony Brook
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- Book:
- Neurologic Differential Diagnosis
- Published online:
- 05 June 2014
- Print publication:
- 17 April 2014, pp xi-xx
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Monitoring Houbara Bustard Chlamydotis undulata macqueenii distribution, populations and time of occurrence within the Abu Dhabi Emirate using a network of local rangers
- Robert Sheldon, Frédéric Launay
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- Journal:
- Bird Conservation International / Volume 8 / Issue 1 / March 1998
- Published online by Cambridge University Press:
- 11 May 2010, pp. 1-9
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The Houbara Bustard is a winter visitor to the United Arab Emirates. Monitoring its population over large areas is difficult, due to the low density of the species and the nature of its habitat. We examined the possibility of using a network of desert rangers in the western region of the Abu Dhabi Emirate to monitor the population, timing of occurrence and distribution of Houbara Bustards in two consecutive winters. Houbara Bustards arrived in Abu Dhabi in September and moved inland towards the south of the country. The last birds were seen in March. Numbers ranged from 56 to 112 in 1994/1995 and 117 to 235 in 1995/1996. Houbara sightings were not evenly distributed within the region, with consistently higher numbers in sand-dune areas. This habitat is not optimal for Houbaras, where, in the past, they were less often encountered. The level of disturbance associated with more favourable habitats may be one reason why the birds are moving to more remote and inaccessible places. The use of a network of local rangers proved to be invaluable for gathering information on the low density Houbara population over a large area and was a very efficient way of monitoring the status of this endangered species.
Wader, gull and tern population estimates for a key breeding and stopover site in Central Kazakhstan
- HOLGER SCHIELZETH, JOHANNES KAMP, GÖTZ EICHHORN, THOMAS HEINICKE, MAXIM A. KOSHKIN, LARS LACHMANN, ROBERT D. SHELDON, ALEXEJ V. KOSHKIN
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- Journal:
- Bird Conservation International / Volume 20 / Issue 2 / June 2010
- Published online by Cambridge University Press:
- 09 March 2010, pp. 186-199
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Population size estimates of waders, gulls and terns passing through or breeding in Central Asia are very scarce, although highly important for global flyway population estimates as well as for targeting local conservation efforts. The Tengiz-Korgalzhyn region is one of the largest wetland complexes in Central Asia. We conducted surveys in this region between 1999 and 2008 and present estimates of population size as well as information on phenology and age structure for 50 species of Charadriiformes. The Tengiz-Korgalzhyn wetlands are especially important for Red-necked Phalaropes Phalaropus lobatus and Ruffs Philomachus pugnax with, respectively, 41% and 13% of their flyway populations using the area during spring migration. The region is also an important post-breeding moulting site for Pied Avocets Recurvirostra avosetta and Black-tailed Godwits Limosa limosa used by, respectively, 5% and 4% of their flyway populations. Besides its key importance as a migratory stopover site, the study area is a key breeding site for the Critically Endangered Sociable Lapwing Vanellus gregarius, the Near Threatened Black-winged Pratincole Glareola nordmanni and for Pallas’s Gull Larus ichthyaetus with 16%, 6% and 5% of their world populations, respectively. We identified 29 individual sites that held more than 1% of the relevant flyway populations of at least one species of Charadriiformes. Including data on other species of waterbirds (mainly waterfowl), there were 93 sites that qualify for Important Bird Areas (IBA). About half of them are protected in a state nature reserve, while an additional 20% are recognised as IBAs. Nevertheless, 28 important sites are currently not recognised as IBAs nor are they protected by other conservation means. These sites require conservation attention.
Population size, breeding performance and habitat use of the Black-winged Pratincole Glareola nordmanni
- JOHANNES KAMP, MAXIM A. KOSHKIN, ROBERT D. SHELDON
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- Journal:
- Bird Conservation International / Volume 19 / Issue 2 / June 2009
- Published online by Cambridge University Press:
- 01 June 2009, pp. 149-163
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The population of the Black-winged Pratincole Glareola nordmanni has declined significantly during the course of the 20th century, resulting in a classification as ‘Near Threatened’ and ‘Endangered’ in the Global and European Red Data Books, respectively. Reasons for the decline are largely unknown due to a lack of information on the breeding ecology of the species. We studied breeding performance and habitat use of the Black-winged Pratincole in two areas in Kazakhstan and evaluated a new world population estimate. Colony size ranged from two to 180 pairs and differed significantly between the study areas. Mean breeding success was 1.30 ± 0.16 (mean ± SE) fledged chicks per breeding pair in Central Kazakhstan, and 0.59 ± 0.13 (mean ± SE) fledged chicks per breeding pair in NE Kazakhstan. Habitat types preferred were intensively grazed natural steppe, abandoned and fallow fields, shores of freshwater and brackish lakes and solonchaks (salt pans). Factors influencing habitat selection were quantified the first time for this species: the probability of occurrence of breeding colonies was highest near human settlements, within 3km of open water and where sward heights were low or intermediate, indicating a reliance on heavy grazing and water.
Using data from six surveys across the whole breeding range, we calculated a new world population estimate of 76,000–95,000 breeding pairs, which is substantially higher than previous estimates. We discuss colony size, habitat use and population trends in the light of changing landscape conditions in the steppe zone and suggest an increase in habitat available to Black-winged Pratincole due to an increase in the area of fallow fields and a change in grazing regimes since the collapse of the Soviet Union in 1991.
On the fine structure of osmosis including three-dimensional pore entrance and exit behaviour
- Zong-Yi Yan, Sheldon Weinbaum, Robert Pfeffer
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- Journal:
- Journal of Fluid Mechanics / Volume 162 / January 1986
- Published online by Cambridge University Press:
- 21 April 2006, pp. 415-438
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This paper presents a detailed quantitative model of osmotic fine structure for both permeable and semi-permeable membranes in dilute bathing solutions. The analysis differs from all previous studies in that it treats for the first time, albeit in an approximate manner, the detailed three-dimensional hydrodynamic interaction of the particles in the entrance and exit regions and the coupling of the convective—diffusive effects in these regions with those in the interior of the pore. Reasonable interpolations between various asymptotic formulas are used to derive the tensorial components of the particle diffusivity and the slip between the fluid and particle phases as functions of position throughout the entire flow field. The solutions show that the entrance and exit regions in the case of permeable membranes can have a significant effect on the osmotic solvent flux q for small particles in short pores although changes in the overall reflection coefficient are small. This is due to the nonlinear sweeping effect of convection at the higher osmotic-flow rates. For semi-permeable membranes the predictions of the model support the hypothesis of Mauro (1957) and Ray (1960) that there is a region of near-discontinuity in pressure and concentration at the plane of the pore entrance and the sweeping effects of convection on the concentration profile are very minor for the dilute solutions studied herein. In contrast, the solutions for the permeable membrane clearly show the existence of three-dimensional unstirred regions which extend two-to-three pore radii from the pore openings. These solutions form the ubstructure of the much thicker one-dimensional unstirred layer described by Dainty (1963) and Pedley et al. (1978). It is shown that when the porosity is low (such as in most biological membranes), the wall concentration in Pedley's solution is the far-field concentration for the entrance/exit solutions presented herein.
The three-dimensional hydrodynamic interaction of a finite sphere with a circular orifice at low Reynolds number
- Zong-Yi Yan, Sheldon Weinbaum, Peter Ganatos, Robert Pfeffer
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- Journal:
- Journal of Fluid Mechanics / Volume 174 / January 1987
- Published online by Cambridge University Press:
- 21 April 2006, pp. 39-68
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This paper proposes a combined multipole-series representation and integral-equation method for solving the low-Reynolds-number hydrodynamic interaction of a finite sphere at the entrance of a circular orifice. This method combines the flexibility of the intergral-equation method in treating complicated geometries and the accuracy and computational efficiency of the multipole-series-representation technique. For the axisymmetric case, the hydrodynamic force has been solved for the difficult case where the sphere intersects the plane of the orifice opening, which could not be treated by previous methods. For the three-dimensional case, the first numerical solutions have been obtained for the spatial variation of the twelve force and torque correction factors describing the translation or rotation of the sphere in a quiescent fluid at a pore entrance or the Sampson flow past a fixed sphere. Restricted by excessive computation time, accurate three-dimensional solutions are presented only for a sphere which is one-half the orifice diameter. However, based on an analysis of the behaviour of the force and torque correction factors for this case, approximate interpolation formulas utilizing the results on or near the orifice axis and in the far field are proposed for other diameter ratios, thus greatly extending the usefulness of the present solution.
Gravitational and zero-drag motion of a sphere of arbitrary size in an inclined channel at low Reynolds number
- Peter Ganatos, Sheldon Weinbaum, Robert Pfeffer
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- Journal:
- Journal of Fluid Mechanics / Volume 124 / November 1982
- Published online by Cambridge University Press:
- 20 April 2006, pp. 27-43
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The strong-interaction theory developed in Ganatos, Weinbaum & Pfeffer (1 9804 and Ganatos, Pfeffer & Weinbaum (1980b) for the normal and parallel creeping motion of a sphere of arbitrary size between two infinite plane-parallel walls is applied to several particle-boundary interaction problems of long-standing interest. The first highly accurate solutions are presented for the slip and angular velocity of a neutrally buoyant sphere carried by the fluid in a Couette or Poiseuille channel flow and the gravitational settling of a non-neutrally buoyant sphere in an inclined channel. The latter problem clearly illustrates the non-isotropy of the frictional resistance tensor on the particle motion. The solutions for the fluid velocity field exhibit an induced circulation extending to infinity fore and aft of the sphere for a neutrally buoyant sphere in Couette flow and an induced back-flow ahead of the sphere for the Poiseuille flow geometry. Approximate but highly accurate solutions are presented for small gap widths between a sphere and the neighbouring boundary, which take account of the influence of the second wall.
An infinite-series solution for the creeping motion through an orifice of finite length
- Zeev Dagan, Sheldon Weinbaum, Robert Pfeffer
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- Journal:
- Journal of Fluid Mechanics / Volume 115 / February 1982
- Published online by Cambridge University Press:
- 20 April 2006, pp. 505-523
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This paper presents an infinite-series solution to the creeping viscous motion of a fluid through low- and moderate-aspect-ratio pores. The flow field is divided into two simply bounded regions: a cylindrical volume bounded by the walls of the pore and the entrance and exit planes, and an infinite half-space outside the pore. Analytic solutions are first obtained in each region for unknown functions representing arbitrary axial and radial velocity profiles at the pore entrance (exit). These unknown functions are then determined by matching the normal and tangential stress at the pore opening.
The results indicate that the velocity profile approaches to within 1·5 per cent of a Poiseuille profile after a short entrance distance of half the pore radius. In the far field the solution matches exactly the streamline pattern for a flow through an orifice of zero thickness obtained by Sampson (1891). The pressure drop across the pore exhibits linear dependence on the aspect ratio and is closely approximated (less than one per cent error) by a simple algebraic expression.
A strong interaction theory for the creeping motion of a sphere between plane parallel boundaries. Part 1. Perpendicular motion
- Peter Ganatos, Sheldon Weinbaum, Robert Pfeffer
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- Journal:
- Journal of Fluid Mechanics / Volume 99 / Issue 4 / 29 August 1980
- Published online by Cambridge University Press:
- 19 April 2006, pp. 739-753
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This paper presents the first ‘exact’ solutions to the creeping-flow equations for the transverse motion of a sphere of arbitrary size and position between two plane parallel walls. Previous solutions to this classical Stokes flow problem (Ho & Leal 1974) were limited to a sphere whose diameter is small compared with the distance of the closest approach to either boundary. The accuracy and convergence of the present method of solution are tested by detailed comparison with the exact bipolar co-ordinate solutions of Brenner (1961) for the drag on a sphere translating perpendicular to a single plane wall. The converged series collocation solutions obtained in the presence of two walls show that for the best case where the sphere is equidistant from each boundary the drag on the sphere predicted by Ho & Leal (1974), using a first-order reflexion theory, is 40 per cent below the true value when the walls are spaced two sphere diameters apart and is one order-of-magnitude lower at a spacing of 1.1 diameters.
A strong interaction theory for the creeping motion of a sphere between plane parallel boundaries. Part 2. Parallel motion
- Peter Ganatos, Robert Pfeffer, Sheldon Weinbaum
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- Journal:
- Journal of Fluid Mechanics / Volume 99 / Issue 4 / 29 August 1980
- Published online by Cambridge University Press:
- 19 April 2006, pp. 755-783
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Exact solutions are presented for the three-dimensional creeping motion of a sphere of arbitrary size and position between two plane parallel walls for the following conditions: (a) pure translation parallel to two stationary walls, (b) pure rotation about an axis parallel to the walls, (c) Couette flow past a rigidly held sphere induced by the motion of one of the boundaries and (d) two-dimensional Poiseuille flow past a rigidly held sphere in a channel. The combined analytic and numerical solution procedure is the first application for bounded flow of the three-dimensional boundary collocation theory developed in Ganatos, Pfeffer & Weinbaum (1978). The accuracy of the solution technique is tested by detailed comparison with the exact bipolar co-ordinate solutions of Goldman, Cox & Brenner (1967a, b) for the drag and torque on a sphere translating parallel to a single plane wall, rotating adjacent to the wall or in the presence of a shear field. In all cases, the converged collocation solutions are in perfect agreement with the exact solutions for all spacings tested. The new collocation solutions have also been used to test the accuracy of existing solutions for the motion of a sphere parallel to two walls using the method of reflexions technique. The first-order reflexion theory of Ho & Leal (1974) provides reasonable agreement with the present results for the drag when the sphere is five or more radii from both walls. At closer spacings first-order reflexion theory is highly inaccurate and predicts an erroneous direction for the torque on the sphere for a wide range of sphere positions. Comparison with the classical higher-order method of reflexions solutions of Faxen (1923) reveals that the convergence of the multiple reflexion series solution is poor when the sphere centre is less than two radii from either boundary.
Solutions have also been obtained for the fluid velocity field. These solutions show that, for certain wall spacings and particle positions, a separated region of closed streamlines forms adjacent to the sphere which reverses the direction of the torque acting on a translating sphere.
A numerical-solution technique for three-dimensional Stokes flows, with application to the motion of strongly interacting spheres in a plane
- Peter Ganatos, Robert Pfeffer, Sheldon Weinbaum
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- Journal:
- Journal of Fluid Mechanics / Volume 84 / Issue 1 / 16 January 1978
- Published online by Cambridge University Press:
- 12 April 2006, pp. 79-111
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This paper describes how the collocation technique previously developed by the authors for treating both unbounded (Gluckman, Pfeffer & Weinbaum 1971; Leichtberg, Weinbaum, Pfeffer & Gluckman 1976) and bounded (Leichtberg, Pfeffer & Weinbaum 1976) multiparticle axisymmetric Stokes flows can be extended to handle a wide variety of non-axisymmetric creeping-motion problems with planar symmetry where the boundaries conform to more than a single orthogonal co-ordinate system. The present paper examines in detail the strong hydrodynamic interaction between two or more closely spaced identical spheres in a plane. The various two-sphere configurations provide a convenient means of carefully testing the accuracy and convergence of the numerical solution technique for three dimensional flow with known exact spherical bipolar solutions.
The important difficulty encountered in applying the collocation technique to multi-particle non-axisymmetric flows is that the selection of boundary points is rather sensitive to the flow orientation. Despite this shortcoming one is able to obtain solutions for the quasi-steady particle velocities and drag for as many as 15 spheres in less than 30 s on an IBM 370/168 computer. The method not only gives accurate global results, but is able to predict the local fluid velocity and to resolve fine features of the flow such as the presence of separated regions of closed streamlines. Time-dependent numerical solutions are also presented for various three-sphere assemblages falling in a vertical plane. These solutions, in which the motion of each sphere is traced for several hundred diameters, are found to be in very good agreement with experimental measurements. The concluding section of the paper describes how the present collocation procedure can be extended to a number of important unsolved three-dimensional problems in Stokes flow with planar symmetry such as the arbitrary off-axis motion of a sphere in a circular cylinder or between parallel walls, or the motion of a neutrally buoyant particle at the entrance to a slit or pore.