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65 Gene-specific risk of syndrome-associated cancers in first-degree relatives of pancreatic cancer patients with pathogenic/likely pathogenic variants
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- Xuan Chen, Kari G. Rabe, Margaret A. Meyer, Jennifer L. Kemppainen, Masayasu Horibe, Shruti Chandra, Shounak Majumder, Gloria M. Petersen
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- Journal:
- Journal of Clinical and Translational Science / Volume 7 / Issue s1 / April 2023
- Published online by Cambridge University Press:
- 24 April 2023, p. 18
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This abstract is based on unpublished data. OBJECTIVES/GOALS: The estimates of unbiased first-degree relatives (FDRs) risk of cancers would enhance genetic counseling of at-risk FDRs in families where the pancreatic cancer (PC) proband carrying a germline variant. This study aims at quantifying gene-specific risks of six cancers among FDRs of PC patients with germline variants in cancer-associated genes. METHODS/STUDY POPULATION: In the prospective, clinic-based Mayo Clinic Biospecimen Resource for Pancreas Research registry, 4,562 PC patients had previously undergone germline genetic testing for pancreatic cancer-associated genes through either research studies or clinical testing. Of these, 234 PC probands were found to carry germline pathogenic/likely pathogenic variants (PLPV) among 9 genes of interest and had provided detailed demographic and cancer data on their FDRs by questionnaire. We focused on six cancer types (ovary, breast, uterus, pancreas, colon, and malignant melanoma) in FDRs as reported by the probands. Standardized incidence ratios were calculated to estimate risk of six cancers among FDRs of PC patients carrying PLPV by gene. RESULTS/ANTICIPATED RESULTS: 1,670 FDRs (mean age 58.1+17.8SD; 48.9% female) were included in the study. We found significantly increased risk of ovarian cancer in female FDRs of PC probands who carry PLPV in BRCA1 (SIR 9.49, 95%CI:3.06-22.14) or BRCA2 (3.72, 95%CI:1.36-8.11), and breast cancer risks were higher with BRCA2 (2.62, 95%CI:1.89-3.54). Uterine cancer risk was increased in FDRs of PC probands who carry PLPV for Lynch Syndrome mismatch repair (MMR) (6.53, 95%CI:2.81-12.86). PC risk was also increased (ATM 4.53, 95% CI:2.69-7.16; BRCA2 3.45, 95%CI:1.72-6.17; CDKN2A 7.38, 95%CI:3.18-14.54; PALB2 5.39, 95%CI:1.45-13.79). Increased colon cancer risk was observed in FDRs of probands who carried MMR PLPV (5.83, 95%CI:3.70-8.75), while melanoma risk was elevated for FDRs of probands with CDKN2A PLPV (7.47, 95%CI:3.97-12.77). DISCUSSION/SIGNIFICANCE: PLPV in nine syndrome-associated genes in PC probands are associated with increased risk of six cancers in FDRs. The findings underscore the importance of risk estimation of various other cancers in PC families for screening, early detection, intervention, and cascade genetic testing.
Crinoid Feeding Strategies: New Insights From Subsea Video And Time-Lapse
- David Meyer, Margaret Veitch, Charles G. Messing, Angela Stevenson
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- 17 February 2021
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- 24 June 2021
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Modern videography provides an ever-widening window into subsea echinoderm life with vast potential for new knowledge. Supported by video evidence throughout, this Element begins with time-lapse video made in 1983 on film, using an off-the-shelf camera, flash, and underwater housings. Although quality has now been significantly improved by digital imagery, films from over thirty years ago captured crinoid feeding behavior previously unknown and demonstrated a great potential to learn about many other aspects of their biology. This sequence is followed by several examples of recent digital videography from submersibles of deep-sea crinoids and remotely operated vehicles (ROVs) (stalked and unstalked), as well as close-up video of crinoids in aquaria. These recent studies enabled a new classification of crinoid arm postures, provided detailed views of food particle capture, and revealed a wide range of behaviors in taxa never before seen in life.
OP152 Level Of Agreement In EUnetHTA Joint Action 3 Early Dialogues
- Judith Fernandez, Chantal Guilhaume, Margaret Galbraith, François Meyer, Chantal Belorgey, Christian Thuillez, Anne d'Andon
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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. 55-56
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Introduction:
A recent article reported a high level of commonality across European Health Technology Assessment bodies’ (HTABs) positions in former parallel scientific advice procedure. Since 2017, the EUnetHTA joint action 3 (JA3) offers a new early dialogue process involving a higher number of European HTABs. The present analysis aims to describe if the JA3 process modified the level of agreement across HTABs.
Methods:A descriptive analysis of the written recommendations provided during every JA3 early dialogues coordinated by the French National Authority for Health (HAS) until November 2017 was conducted. The level of commonality for each HTAB position identified was assessed globally and by domain (population, comparator, outcomes, study design and health economics) and classified as follows: “full agreement” if all HTABs had the same position, “partial agreement” if more than half HTABs had the same position and “disagreement” in all other cases.
Results:Four JA3 early dialogues were performed until November 2017: two in oncology, one in neurology and one in metabolic disorders. Between five and nine HTABs from eleven European countries participated. A total of forty-six positions were identified in these four early dialogues: ten on population, five on comparator, fifteen on outcomes, four on study design and twelve on health economics. Of the forty-six positions, full agreement was reached for twenty-eight positions, partial agreement for seventeen positions and only one disagreement was observed. The level of full agreements was highest for questions on comparators (five out of five) and population (nine out of ten) and lower for questions on health economics (six out of 12).
Conclusions:Although the JA3 process substantially increased the number of HTABs participating in the early dialogues, this descriptive analysis suggests that the level of agreement remains very high. This may be facilitated by the high level of dialogue and coordination between HTAB ensured by the EUnetHTA process.
Elderly Latino community members make an educational video: an academic-community collaboration to promote memory evaluations
- Judith Neugroschl, Margaret C. Sewell, Mari Umpierre, Raquel Rodriguez, Laura Meyers, Stephanie Kranes, Carlos Aldrete, Alma Collazo, Licet Valois, Mary Sano
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- Journal:
- International Psychogeriatrics / Volume 31 / Issue 7 / July 2019
- Published online by Cambridge University Press:
- 15 October 2018, pp. 989-995
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Objectives:
To develop an educational video to reach elderly Latinos in order to improve understanding and encourage evaluation of cognitive changes by 1) using focus groups to identify dementia knowledge gaps, health communication preferences and trusted advisors for health concerns; 2) collaborating with elderly Latino community members to create a video; and 3) collecting survey data regarding community response to the video.
Design:Grounded theory qualitative approach using focus groups; collaborative community based model to create the video and anonymous survey at community screenings.
Setting:Community senior centers in East Harlem, New York.
Participants:A team of low-income mono and bilingual elderly Latino community residents, researchers, clinicians, and a film professional.
Measurements:Thematic analysis of focus group transcripts; three item survey.
Results:A collaboratively produced video and initial assessment in 49 Latino elders that indicated the video had a positive effect on interest in obtaining a brief memory screening at outreach events (71%).
Conclusions:The project demonstrates the feasibility of this interdisciplinary partnership to create a culturally and linguistically sensitive video to promote service use concerning memory loss and cognitive evaluations among elderly Latinos. Initial survey results suggested a positive response and an increase in interest in memory screening.
Safety of tracheal intubation in the presence of cardiac disease in paediatric ICUs
- Eleanor A. Gradidge, Adnan Bakar, David Tellez, Michael Ruppe, Sarah Tallent, Geoffrey Bird, Natasha Lavin, Anthony Lee, Vinay Nadkarni, Michelle Adu-Darko, Jesse Bain, Katherine Biagas, Aline Branca, Ryan K. Breuer, Calvin Brown III, Kris Bysani, Guillaume Emeriaud, Sandeep Gangadharan, John S. Giuliano, Jr, Joy D. Howell, Conrad Krawiec, Jan Hau Lee, Simon Li, Keith Meyer, Michael Miksa, Natalie Napolitano, Sholeen Nett, Gabrielle Nuthall, Alberto Orioles, Erin B. Owen, Margaret M. Parker, Simon Parsons, Lee A. Polikoff, Kyle Rehder, Osamu Saito, Ron C. Sanders, Jr, Asha Shenoi, Dennis W. Simon, Peter W. Skippen, Keiko Tarquinio, Anne Thompson, Iris Toedt-Pingel, Karen Walson, Akira Nishisaki, For National Emergency Airway Registry for Children (NEARKIDS) Investigators and Pediatric Acute Lung Injury and Sepsis Investigators (PALISI)
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- Journal:
- Cardiology in the Young / Volume 28 / Issue 7 / July 2018
- Published online by Cambridge University Press:
- 25 April 2018, pp. 928-937
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Introduction
Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methodsWe sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
ResultsA total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
ConclusionsThe overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
VP25 African Countries Are Working Together To Enhance Medicine Use
- Amos Massele, Daniel Afriyie, Johanita Burger, Charles Ezenduka, Joseph Fadare, Aubrey Kalungia, Dan Kibuule, Johanna Meyer, Olayinka Ogunleye, Margaret Oluka, Ilse Truter, Brian Godman
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- Journal:
- International Journal of Technology Assessment in Health Care / Volume 33 / Issue S1 / 2017
- Published online by Cambridge University Press:
- 12 January 2018, pp. 157-158
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INTRODUCTION:
The socioeconomic burden of diseases is increasing in Africa. For instance in 2011, 70 percent of the world's human immunodeficiency virus (HIV) population resided in sub-Sahara Africa. There are also growing rates of Antimicrobial Resistance (AMR), which necessitates newer more expensive antibiotics adding to costs. There is also a growing burden of non-communicable diseases (NCDs), three out of four patients with hypertension currently live in low and middle income countries (LMICs), with prevalence rates up to 30 to 45 percent among adults in Africa. Alongside this, up to 70 percent of total healthcare expenditure is spent on medicines in LMICs; much of this out-of-pocket. Consequently, there is an urgent need to strengthen collaborative research to improve medicine use.
METHODS:Summary of groups working together in Africa including the Medicines Utilisation Research in Africa (MURIA) group.
RESULTS:African Strategies for Health identifies and advocates best practices, as well as works with others to develop sustainable solutions. Pharmacology for Africa (PharfA) organises and promotes pharmacology on the African continent, including research in clinical pharmacology, alongside the International Union of Basic and Clinical Pharmacology (IUPHAR) sub-division. International Society for Pharmacoeconomics and Outcomes Research (ISPOR) Africa co-ordinates activities from the different African country chapters. The South African Health Technology Assessment Society (SAHTAS) is a scientific and professional society for all those who produce, use, or encounter Health Technology Assessment (HTA) in Southern Africa, and the World Health Organization (WHO) International and Regional groups are improving antibiotic drug utilization capabilities in Africa. The MURIA group was established in 2015 (1). Ongoing collaborative research includes (i) initiatives to optimize antibiotic use; (ii) methods to enhance adherence to anti-infective prescribing guidance, (iii) approaches to improve adherence to HIV and NCDs; (iv) researching current anti-hypertensive utilization patterns and knowledge; (v) approaches to enhance Drugs and Therapeutic Committees (DTC) activities, and (vi) strengthening medicine utilization capabilities (2,3). These activities have already strengthened research ties across Africa.
CONCLUSIONS:A number of groups are already working across Africa to enhance appropriate medicine use, and should continue. Ongoing MURIA activities include antibiotic point-prevalence studies, ongoing research into infectious diseases, NCDs and DTCs including adherence as well as the third workshop and symposium in Namibia in 2017.
Contributors
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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 Jimmy N. Avari, Joshua Berman, David A. Brent, Benjamin D. Brody, Carolyn Broudy, Gerard E. Bruder, Deborah L. Cabaniss, Megan S. Chesin, Melissa P. DelBello, Davangere P. Devanand, Jordan W. Eipper, Jean Endicott, Eric A. Fertuck, Michael B. First, Benicio N. Frey, Emily Gastelum, Lucas Giner, Barbara L. Gracious, David J. Hellerstein, Aerin M. Hyun, David A. Kahn, Jürgen Kayser, S. Aiden Kelly, James H. Kocsis, Robert A. Kowatch, Gonzalo Laje, Martin J. Lan, Kyle A. B. Lapidus, Frances R. Levin, Sarah H. Lisanby, J. John Mann, Sanjay J. Mathew, Patrick J. McGrath, Francis J. McMahon, Barnett S. Meyers, Luciano Minuzzi, Diana E. Moga, Philip R. Muskin, Edward V. Nunes, Maria A. Oquendo, Ramin V. Parsey, Joan Prudic, Annie E. Rabinovitch, Drew Ramsey, Steven P. Roose, Moacyr A. Rosa, Bret R. Rutherford, Roberto Sassi, Peter A. Shapiro, Margaret G. Spinelli, Barbara H. Stanley, Meir Steiner, Jonathan W. Stewart, M. Elizabeth Sublette, Craig E. Tenke, Jiuan Su Terman, Michael Terman, Michael E. Thase, Helen Verdeli, Myrna M. Weissman
- Edited by J. John Mann, Columbia University, New York
- Edited in association with Patrick J. McGrath, Columbia University, New York, Steven P. Roose, Columbia University, New York
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- Clinical Handbook for the Management of Mood Disorders
- Published online:
- 05 May 2013
- Print publication:
- 09 May 2013, pp vii-x
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Shape effects on turbulent modulation by large nearly neutrally buoyant particles
- Gabriele Bellani, Margaret L. Byron, Audric G. Collignon, Colin R. Meyer, Evan A. Variano
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- Journal of Fluid Mechanics / Volume 712 / 10 December 2012
- Published online by Cambridge University Press:
- 27 September 2012, pp. 41-60
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We investigate dilute suspensions of Taylor-microscale-sized particles in homogeneous isotropic turbulence. In particular, we focus on the effect of particle shape on particle–fluid interaction. We conduct laboratory experiments using a novel experimental technique to simultaneously measure the kinematics of fluid and particle phases. This uses transparent particles having the same refractive index as water, whose motion we track via embedded optical tracers. We compare the turbulent statistics of a single-phase flow to the turbulent statistics of the fluid phase in a particle–laden suspension. Two suspensions are compared, one in which the particles are spheres and the other in which they are prolate ellipsoids with aspect ratio 2. We find that spherical particles at volume fraction ${\phi }_{v} = 0. 14\hspace{0.167em} \% $ reduce the turbulent kinetic energy (TKE) by 15 % relative to the single-phase flow. At the same volume fraction (and slightly smaller total surface area), ellipsoidal particles have a much smaller effect: they reduce the TKE by 3 % relative to the single-phase flow. Spectral analysis shows the details of TKE reduction and redistribution across spatial scales: spherical particles remove energy from large scales and reinsert it at small scales, while ellipsoids remove relatively less TKE from large scales and reinsert relatively more at small scales. Shape effects are far less evident in the statistics of particle rotation, which are very similar for ellipsoids and spheres. Comparing these with fluid enstrophy statistics, we find that particle rotation is dominated by velocity gradients on scales much larger than the particle characteristic length scales.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- Book:
- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
- Print publication:
- 20 September 2010, pp xi-xliv
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11 - Price competition vs. quantity competition: the role of uncertainty
- Edited by Andrew F. Daughety, University of Iowa
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- Book:
- Cournot Oligopoly
- Published online:
- 07 September 2009
- Print publication:
- 27 January 1989, pp 229-262
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Summary
We analyze the Nash equilibria of a one-stage game in which the nature of the strategic variables (prices or quantities) is determined endogenously. Duopolists producing differentiated products simultaneously choose either a quantity to produce or a price to charge. In the absence of exogenous uncertainty, there exist four types of equilibria with differing levels of output: (price, price), (quantity, quantity), (price, quantity), and (quantity, price). The multiplicity of equilibria stems from each firm's indifference between setting price and quantity, given its conjecture about its rival's strategy. But exogenous uncertainty about market demands, which makes firms uncertain about their residual demands, even in equilibrium, gives firms strict preferences between setting price and quantity. As a result, the number of equilibria is reduced. When uncertainty is exogenous, we analyze the effect of the slope of marginal costs, the nature of the demand disturbance, and the curvature of demand on firms' propensities to compete with price or quantity as the strategic variable. These three factors are likely to influence the nature and intensity of oligopolistic competition.
Introduction
Economists using games to represent oligopolistic competition debated the relative merits of models using prices or quantities as firms' strategic variables from as early as Bertrand's (1883) criticism of Cournot (1838). The extent to which firms can choose price or quantity must, of course, crucially affect the nature of competition. If they have some choice, however, the extent to which firms want to choose price or quantity may be important.