31 results
Simulated-Use Polytetrafluorethylene Biofilm Model: Repeated Rounds of Complete Reprocessing Lead to Accumulation of Organic Debris and Viable Bacteria
- Michelle J. Alfa, Harminder Singh, Zoann Nugent, Donald Duerksen, Gale Schultz, Carol Reidy, Pat DeGagne, Nancy Olson
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 38 / Issue 11 / November 2017
- Published online by Cambridge University Press:
- 17 October 2017, pp. 1284-1290
- Print publication:
- November 2017
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OBJECTIVE
Biofilm has been implicated in bacterial persistence and survival after endoscope reprocessing. In this study, we assessed the impact of different methods of reprocessing on organic residues and viable bacteria after repeated rounds of biofilm formation when each was followed by full reprocessing.
METHODSATS-2015, an artificial test soil containing 5–8 Log10 colony-forming units (CFU) of Enterococcus faecalis and Pseudomonas aeruginosa, was used to form biofilm in polytetrafluroethylene channels overnight on 5 successive days. Each successive day, full pump-assisted cleaning using bristle brushes or pull-through devices in combination with enzymatic or nonenzymatic detergents followed by fully automated endoscope reprocessor disinfection using peracetic acid was performed. Residuals were visualized by scanning electron microscopy (SEM). Destructive testing was used to assess expected cutoffs for adenosine triphosphate (ATP; <200 relative light units), protein (<2 µg/cm2), and viable bacteria count (0 CFU).
RESULTSProtein residuals were above 2 µg/cm2, but ATP residuals were <200 relative light units for all methods tested. Only when enzymatic cleaner was used for cleaning were there no viable bacteria detected after disinfection irrespective of whether bristle brushes or pull-through devices were used. SEM revealed that some residual debris remained after all reprocessing methods, but more residuals were detected when a nonenzymatic detergent was used.
CONCLUSIONSSurviving E. faecalis and P. aeruginosa were only detected when the non-enzymatic detergent was used, emphasizing the importance of the detergent used for endoscope channel reprocessing. Preventing biofilm formation is critical because not all current reprocessing methods can reliably eliminate viable bacteria within the biofilm matrix.
Infect Control Hosp Epidemiol 2017;38:1284–1290
Temporal and Spatial Patterns in Utilization of Mental Health Services During and After Hurricane Sandy: Emergency Department and Inpatient Hospitalizations in New York City
- Fangtao Tony He, Nneka Lundy De La Cruz, Donald Olson, Sungwoo Lim, Amber Levanon Seligson, Gerod Hall, Jillian Jessup, Charon Gwynn
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- Journal:
- Disaster Medicine and Public Health Preparedness / Volume 10 / Issue 3 / June 2016
- Published online by Cambridge University Press:
- 13 June 2016, pp. 512-517
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Objective
Hurricane Sandy made landfall on October 29, 2012, causing a coastal storm surge and extensive flooding, which led to the closure of several health care facilities in New York City (NYC) and prolonged interruptions in service delivery. The impact on mental health–related emergency department (ED) and inpatient hospital service utilization was studied.
MethodsData came from the New York Statewide Planning and Research Cooperative System. We obtained mental health–related data among NYC residents from 2010 to 2013. Patients were grouped into 5 geographic areas, including service areas of closed hospitals, the Hurricane Sandy evaluation zone, and all of NYC. The Farrington method was used to detect increases in ED visits and hospitalizations for the post-Sandy period.
ResultsOpen hospitals experienced a substantial increase in psychiatric ED visits from patients living in the service areas of closed hospitals. This surge in psychiatric ED visits persisted for 4 to 6 months after Hurricane Sandy. However, the increase in psychiatric hospitalizations was observed for 1 to 3 months.
ConclusionsSeveral NYC hospitals received a substantially larger number of ED patients from service areas of closed hospitals after Hurricane Sandy, unlike other hospitals that experienced a decrease. Because of potential surges in the number of psychiatric ED visits, resource allocation to hospitals should be considered. (Disaster Med Public Health Preparedness. 2016;10:512–517)
Spatial Shift in the Utilization of Mental Health Services After Hurricane Sandy Among New York City Residents Enrolled in Medicaid
- Gerod Hall, Jillian Jessup, Sungwoo Lim, Donald Olson, Amber Levanon Seligson, Fangtao Tony He, Nneka De La Cruz, Charon Gwynn
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- Journal:
- Disaster Medicine and Public Health Preparedness / Volume 10 / Issue 3 / June 2016
- Published online by Cambridge University Press:
- 29 April 2016, pp. 420-427
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Objective
Closure of several New York City (NYC) hospitals after Hurricane Sandy caused an unanticipated, extended surge in patient demand at open hospitals. This study identified hospitals with a significant increase in mental-health-related emergency department, inpatient, and outpatient visits from Medicaid patients displaced by Hurricane Sandy.
MethodsNYC Medicaid patients were classified into non-mutually-exclusive geographic categories corresponding to residence in areas served by Bellevue Hospital Center and Coney Island Hospital, the hurricane impact area, and all of NYC. For each geographic region, we compared the observed to the expected number of service visits in the 6 months after the storm. The expected number of visits was calculated from 2-year trends in mental health claims.
ResultsTwenty-four facilities in all 5 NYC boroughs experienced patient redistribution from storm-affected areas. Eighteen facilities had a concurrent surge in total Medicaid patients, which suggested that redistribution had a greater impact on resource use at these locations.
ConclusionsThe redistribution of Medicaid patients after Hurricane Sandy increased mental health service utilization at facilities not near flooded areas. Our findings can aid in surge capacity planning and thereby improve the continuity of mental health care after a natural disaster. (Disaster Med Public Health Preparedness. 2016;10:420–427)
Notes on contributors
- Edited by Ben Akrigg, University of Toronto, Rob Tordoff, York University, Toronto
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- Book:
- Slaves and Slavery in Ancient Greek Comic Drama
- Published online:
- 05 February 2013
- Print publication:
- 31 January 2013, pp x-xii
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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. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. Nicholson, George W. E. Nickelsburg, Tatyana Nikolskaya, Damayanthi M. A. Niles, Bertil Nilsson, Nyambura Njoroge, Fidelis Nkomazana, Mary Beth Norton, Christian Nottmeier, Sonene Nyawo, Anthère Nzabatsinda, Edward T. Oakes, Gerald O'Collins, Daniel O'Connell, David W. Odell-Scott, Mercy Amba Oduyoye, Kathleen O'Grady, Oyeronke Olajubu, Thomas O'Loughlin, Dennis T. Olson, J. Steven O'Malley, Cephas N. Omenyo, Muriel Orevillo-Montenegro, César Augusto Ornellas Ramos, Agbonkhianmeghe E. Orobator, Kenan B. Osborne, Carolyn Osiek, Javier Otaola Montagne, Douglas F. Ottati, Anna May Say Pa, Irina Paert, Jerry G. Pankhurst, Aristotle Papanikolaou, Samuele F. Pardini, Stefano Parenti, Peter Paris, Sung Bae Park, Cristián G. Parker, Raquel Pastor, Joseph Pathrapankal, Daniel Patte, W. Brown Patterson, Clive Pearson, Keith F. Pecklers, Nancy Cardoso Pereira, David Horace Perkins, Pheme Perkins, Edward N. Peters, Rebecca Todd Peters, Bishop Yeznik Petrossian, Raymond Pfister, Peter C. Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. 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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17 - The use of EEG in assessing acute and chronic brain damage in the newborn
- from Section 3 - Diagnosis of the infant with brain injury
- Edited by David K. Stevenson, Stanford University School of Medicine, California, William E. Benitz, Stanford University School of Medicine, California, Philip Sunshine, Stanford University School of Medicine, California, Susan R. Hintz, Stanford University School of Medicine, California, Maurice L. Druzin, Stanford University School of Medicine, California
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- Fetal and Neonatal Brain Injury
- Published online:
- 12 January 2010
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- 18 June 2009, pp 196-208
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Summary
Introduction
The goal of this chapter is to help the reader understand the fundamentals of neonatal electroencephalography (EEG), including the source of EEG signals and the technical aspects of a well-performed EEG. Particular attention will be paid to (1) maturational features which correlate with the infant's conceptional age, (2) abnormal findings indicative of encephalopathies of various causes, and (3) the value of the EEG in determining the prognosis for normal and abnormal neurological outcome. The role of EEG in neonatal seizures is covered more thoroughly in Chapter 43.
Value of the EEG
The EEG is a valuable tool for assessing neonatal brain function. It has unique properties compared to many other diagnostic tests of brain function. It can resolve temporal aspects of brain function more effectively than computed tomography (CT), magnetic resonance imaging (MRI), or even the bedside neurological examination. There is no other test that can so precisely discriminate between epileptic seizures and non-epileptic events in the neonate. It provides information about the severity of brain dysfunction (encephalopathy). Serial EEGs provide information about the course and effectiveness of treatment. Sometimes the EEG helps distinguish between various etiologies of encephalopathy.
Indication for EEG
An EEG in the neonate should be considered when questions arise regarding the cause of a child's abnormal neurological responses.
10 - Lagrangian biophysical dynamics
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- By Donald B. Olson, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, USA
- Edited by Annalisa Griffa, University of Miami, A. D. Kirwan, Jr., University of Delaware, Arthur J. Mariano, University of Miami, Tamay Özgökmen, University of Miami, H. Thomas Rossby, University of Rhode Island
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- Lagrangian Analysis and Prediction of Coastal and Ocean Dynamics
- Published online:
- 07 September 2009
- Print publication:
- 10 May 2007, pp 275-348
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Summary
The use of a particle-following or Lagrangian perspective to follow the dynamics of life in the sea is explored from a variety of perspectives. The discussion begins with the consideration of the energetics of marine organisms and a demonstration that mean field models fail to adequately describe the life of large marine fishes in the sense that they require sizable, > 100–1000 X aggregation of prey over the average biomass density in the ocean. In place of a mean field model in time a structured population model where populations are dependent on space, time, age, and their metabolism is derived. Having introduced the structured model it is then argued that it is impractical to use such a model except in a Lagrangian frame. Methods for coupling these models in a Lagrangian description of the marine environment are then discussed. This section of the manuscript ends with an appraisal of the amount of spatial aggregation required to support large pelagic fishes such as swordfish and tunas. The second portion of the paper goes on to provide examples of trajectories in different marine environments including boundary currents, mesoscale eddy fields and fronts, and the coastal environment. An emphasis on the dynamics of trajectories at various trophic levels provides insights on aggregation mechanisms and rates.
The last two sections introduce methods of modeling population structure with Lagrangian trajectories.
21 - The use of the EEG in assessing acute and chronic brain damage in the newborn
- from Part III - Diagnosis of the Infant with Asphyxia
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- By Donald M. Olson, Stanford University Medical Center, Stanford, CA, USA, Jin S. Hahn, Stanford University Medical Center, Stanford, CA, USA
- Edited by David K. Stevenson, Stanford University School of Medicine, California, William E. Benitz, Stanford University School of Medicine, California, Philip Sunshine, Stanford University School of Medicine, California
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- Fetal and Neonatal Brain Injury
- Published online:
- 10 November 2010
- Print publication:
- 06 February 2003, pp 425-445
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Summary
Introduction
The goal of this chapter is to help the reader understand the fundamentals of neonatal electroencephalogram (EEG), including the source of EEG signals and the technical aspects of a well-performed EEG. Particular attention will be paid to: (1) maturational features which correlate with the infant's conceptional age; (2) abnormal findings indicative of encephalopathies of various causes; and (3) value of the EEG in determining the prognosis for normal and abnormal neurological outcome. The role of EEG in neonatal seizures is covered more thoroughly in Chapter 37.
Value of the EEG
The EEG is a valuable tool for assessing neonatal brain function. It has unique properties compared to many other diagnostic tests of brain function. For example, it can resolve temporal aspects of brain function more effectively than computed tomography (CT), magnetic resonance imaging (MRI), or even the bedside neurological examination. There is no other test that can so precisely discriminate between epileptic seizures and nonepileptic events in the neonate. It provides information about the severity of brain dysfunction (encephalopathy). Serial EEGs provide information about the course and effectiveness of treatment. Sometimes the EEG helps distinguish between various etiologies of encephalopathy as well.
Indication for EEG
An EEG in the neonate should be considered when questions arise regarding the cause of the child's abnormal neurological responses. There are many scenarios in which the EEG provides much needed information that is otherwise difficult or impossible to obtain.
Mantle Convection in the Earth and Planets
- Gerald Schubert, Donald L. Turcotte, Peter Olson
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- Published online:
- 15 December 2009
- Print publication:
- 24 September 2001
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Mantle Convection in the Earth and Planets is a comprehensive synthesis of all aspects of mantle convection within the Earth, the terrestrial planets, the Moon, and the Galilean satellites of Jupiter. The book includes up-to-date discussions of the latest research developments that have revolutionized our understanding of the Earth and the planets. It is suitable as a text for graduate courses in geophysics and planetary physics, and as a supplementary reference for use at the undergraduate level. It is also an invaluable review for researchers in the broad fields of the Earth and planetary sciences including seismologists, tectonophysicists, geodesists, mineral physicists, volcanologists, geochemists, geologists, mineralogists, petrologists, paleomagnetists, planetary geologists, and meteoriticists. The book features a comprehensive index, an extensive reference list, numerous illustrations (many in color) and major questions that focus the discussion and suggest avenues of future research.
8 - Approximate Solutions
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Summary
Introduction
The linear stability analysis presented in the last chapter gives the critical Rayleigh number for the onset of thermal convection under a variety of conditions. However, because the governing equations have been linearized, the solutions cannot predict the magnitude of finite-amplitude convective flows. In order to do this it is necessary to retain nonlinear terms in the governing equations.
Even in the simplest thermal convection problems the governing equations are sufficiently complex that analytical solutions cannot be found. There are basically two methods for obtaining nonlinear solutions. The first is to make approximations and the second is to obtain fully numerical solutions. We will address the former method in this chapter and the latter method in the subsequent two chapters.
In this chapter we will consider four approximations used to obtain a better understanding of thermal convection. We first consider an eigenmode expansion of the basic equations. This approach provides one of the methods used to obtain fully numerical solutions. However, in this chapter we consider only severe truncations of the full set of eigenmode equations. Retention of only the lowest-order nonlinear terms leads to the Lorenz (1963) equations. This set of equations is of great interest because its solution was the first demonstration of deterministic chaos. In this approximate approach we address the question:
Question 8.1: Is mantle convection chaotic?
This questions leads directly to a second question:
Question 8.2: Is mantle convection turbulent?
The second approximate approach we consider is boundary layer theory. This approach reproduces the basic structure of thermal convection cells at high Rayleigh numbers. The third approach is the mean field approximation.
Subject Index
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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3 - Structure and Composition of the Mantle
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Summary
Introduction
In this chapter we review what is currently known about the structure and the bulk composition of the mantle, with emphasis on how these may influence the style of convection, and how they may be influenced by it. Brief descriptions of the crust and the core are also included, again with an emphasis on those aspects of each region most germane to mantle convection. There are several monographs dealing with Earth structure and composition in a general context, e.g., Ringwood (1975, 1979) and Anderson (1989).
The study of mantle structure is by tradition the province of seismology, while mantle composition has historically been a subject for high-pressure and high-temperature mineralogy, petrology, and geochemistry. A great many important advances have recently been made in these areas, with the result that the studies of mantle composition, structure, and dynamics are now closely related. New findings from seismology, mineral physics, and isotope geochemistry are quickly applied as constraints on models of mantle dynamics. There are also interactions in the other direction. Each new step in understanding the physics of convection is quickly incorporated into new interpretations of mantle structure. This interdisciplinary style of research is perhaps the single most important reason for the emerging view of the deep Earth as a unified physical and chemical system.
Spherically Averaged Earth Structure
The determination of elastic parameters and density throughout the Earth using observations of seismic waves and other constraints is the prototype inverse problem in geophysics. Like many inverse problems, it is formally nonunique and suffers from practical difficulties such as incomplete sampling and errors in the data.
Contents
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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14 - Convection in the Interiors of Solid Planets and Moons
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Introduction
Space missions have provided extensive information on the other planets and the planetary satellites of the solar system. Like the individual islands in an archipelago, the terrestial planets share many characteristics and yet retain striking individuality. For example, it appears that active plate tectonics is unique to the Earth. In contrast, the Moon and Mercury have continuous lithospheres, with surfaces shaped largely by impacts and volcanic processes. Although impact cratering and volcanism have also been prevalent on Mars, its surface has also been modified by its atmosphere and the flow of a surface fluid, presumably water. Cloud-covered Venus has been exposed to the eyes of Earth-based and spacecraft radar systems. Cratering and volcanism have apparently left their marks on its surface, but there is no direct evidence of plate tectonic features such as extensive ridge or trench systems. The Galilean satellites of Jupiter are different from the inner planets and each other in puzzling ways. Ganymede and Callisto are icy satellites (half ice and half rock) whose surfaces have been modified by impacts, and, in the case of Ganymede, by tectonism. Callisto's surface shows no signs of endogenic activity, while Ganymede's surface shows no evidence of plate tectonics. Both of these Jovian moons have continuous water ice lithospheres. Europa is a mainly silicate moon of Jupiter, but Europa also has an outer layer of water ice/liquid. The surface of Europa is covered by ice, but there is a possibility that a liquid water ocean may exist beneath the ice. Europa's surface has been altered by impacts, tectonism, and cryovolcanism, but there is no evidence of global plate tectonics. Io is a silicate body, apparently lacking water.
Author Index
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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2 - Plate Tectonics
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Introduction
During the 1960s there were a wide variety of studies on continental drift and its relationship to mantle convection. One of the major contributors was J. Tuzo Wilson. Wilson (1963a, b, 1965a, b) used a number of geophysical arguments to delineate the general movement of the ocean floor associated with seafloor spreading. He argued that the age progression of the Hawaiian Islands indicated movement of the Pacific plate. He showed that earthquakes on transform faults required seafloor spreading at ridge crests. During this same period other geophysicists outlined the general relations between continental drift and mantle convection (Orowan, 1964, 1965; Tozer, 1965a;Verhoogen, 1965). Turcotte and Oxburgh (1967) developed a boundary layer model for thermal convection and applied it to the mantle. According to this model, the oceanic lithosphere is associated with the cold upper thermal boundary layer of convection in the mantle; ocean ridges are associated with ascending convection in the mantle and ocean trenches are associated with the descending convection of the cold upper thermal boundary layer into the mantle. Despite these apparently convincing arguments, it was only with the advent of plate tectonics in the late 1960s that the concepts of continental drift and mantle convection became generally accepted.
Plate tectonics is a model in which the outer shell of the Earth is broken into a number of thin rigid plates that move with respect to one another. The relative velocities of the plates are of the order of a few tens of millimeters per year. Volcanism and tectonism are concentrated at plate boundaries.
12 - Chemical Geodynamics
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Introduction
Much can be learned about the evolution of the Earth by considering the fluid dynamics of mantle convection and the associated thermal problems. However, chemical effects play a crucial role. Volcanism extracts some elements preferentially and can result in chemical buoyancy. Volcanic differentiation also preferentially extracts the radiogenic elements from the mantle into the continental crust.
In order to understand how volcanic processes influence mantle convection, it is necessary to have a general understanding of the major element petrology. However, both trace element studies and isotope studies provide important constraints. Partial melting of mantle rock concentrates incompatible elements into the resulting magma, but isotope ratios remain unaffected. Thus isotope systematics provide quantitative constraints on the long-term evolution of the mantle and processes such as the convective mixing of subducted lithosphere. In this chapter we will discuss some of these isotope families, observations of isotope ratios in rocks and in the atmosphere, and the implications for mantle convection. We will call this chemical geodynamics (Allègre, 1982, 1987). A general treatment of the use of isotopes in geology has been given by Faure (1986) and by Dickin (1995).
Geochemical Reservoirs
The primary geochemical cycle of the solid Earth is directly associated with plate tectonics and mantle convection; it is illustrated schematically in Figure 12.1. This is a box model in which the principal geochemical reservoirs are included. These are the core, the mantle, the oceanic crust, the continental crust, the oceans, and the atmosphere. In terms of the formation of the Earth, the mantle was the primary reservoir. The core was formed by the differentiation of the dense iron-rich components.
5 - Viscosity of the Mantle
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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13 - Thermal History of the Earth
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Summary
Introduction
Mantle convection plays an essential role in determining the evolution of the Earth's temperature through geologic time because it is the primary mechanism by which the Earth transfers heat from its deep interior to its surface. Once the internally generated heat reaches the surface it is transferred to the ocean–atmosphere system by a variety of processes including conduction and hydrothermal circulation through the oceanic crust and is eventually radiated to space. From the perspective of studying the changes in the Earth's interior temperature over geologic time, we can ignore the relatively rapid transport of internal heat through the atmosphere and oceans and assume that all heat delivered to the Earth's surface from below immediately escapes the Earth. The heat lost through the Earth's surface tends to cool the interior, and heat produced within the Earth by the decay of radioactive elements tends to warm it. The thermal evolution of the Earth is a consequence of the competition between internal energy sources producing heat and mantle convection removing it. A quantitative description of the Earth's thermal history is the application of basic energy conservation in a convecting mantle.
While the basic approach to modeling the Earth's thermal history is straightforward, its implementation is a major challenge because of the complexity of a realistic model and available computer resources that limit detailed numerical calculations of three-dimensional, time-dependent convection at the very high Rayleigh numbers applicable to the Earth's present mantle and at the even higher Rayleigh numbers appropriate to the Earth's early mantle.
7 - Linear Stability
- Gerald Schubert, University of California, Los Angeles, Donald L. Turcotte, Cornell University, New York, Peter Olson, The Johns Hopkins University
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Summary
Introduction
In this chapter we will be concerned with the onset of thermal convection when the fluid is heated just enough that weak convective motions begin to take over from conduction or radiation and transfer some of the heat. We will assume that the onset of convection occurs as a bifurcation from a motionless conductive state. We treat the onset of convection as a problem in the stability of the basic motionless state, i.e., we subject the basic state to perturbations of temperature and velocity and determine conditions under which the perturbations decay or amplify. The onset of convection corresponds to the state in which perturbations have zero growth rate.
If perturbations have a negative growth rate, i.e., if they decay, the basic motionless state is stable and heat is transported conductively. If perturbations have a positive growth rate, they amplify and establish a state of motion in which heat is partly transported convectively. We subject the basic state to perturbations of infinitesimal amplitude. In this case the stability problem can be linearized in the sense that quadratic and higher order products of perturbation quantities can be neglected compared to linear order perturbation quantities.
The linear stability or onset of convection problem is a classic problem with a large literature (see, e.g. Chandrasekhar, 1961). Although mantle convection is a highly nonlinear phenomenon, the linearized stability problem is relevant because it is amenable to analytical description and it contains much of the physics of the nonlinear convective state.
Summary of Basic Equations
The basic equations governing the onset of thermal convection are the conservation equations of mass, momentum, and energy discussed in Chapter 6.