33 results
Analysis of infections among patients with historical culture positive for extended-spectrum beta-lactamase (ESBL)–producing Escherichia coli or Klebsiella pneumoniae: Is ESBL-targeted therapy always needed?
- Tyler J. Stone, Michael DeWitt, James W. Johnson, James R. Beardsley, Iqra Munawar, Elizabeth Palavecino, Vera P. Luther, Christopher A. Ohl, John C. Williamson
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- Journal:
- Antimicrobial Stewardship & Healthcare Epidemiology / Volume 3 / Issue 1 / 2023
- Published online by Cambridge University Press:
- 08 March 2023, e47
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Objective:
Among patients with a history of ESBL infection, uncertainty remains regarding whether all of these patients require ESBL-targeted therapy when presenting with a subsequent infection. We sought to determine the risks associated with a subsequent ESBL infection to help inform empiric antibiotic decisions.
Methods:A retrospective cohort study of adult patients with positive index culture for Escherichia coli or Klebsiella pneumoniae (EC/KP) receiving medical care during 2017 was conducted. Risk assessments were performed to identify factors associated with subsequent infection caused by ESBL-producing EC/KP.
Results:In total, 200 patients were included in the cohort, 100 with ESBL-producing EC/KP and 100 with ESBL-negative EC/KP. Of 100 patients (50%) who developed a subsequent infection, 22 infections were ESBL-producing EC/KP, 43 were other bacteria, and 35 had no or negative cultures. Subsequent infection caused by ESBL-producing EC/KP only occurred when the index culture was also ESBL-producing (22 vs 0). Among those with ESBL-producing index culture, the incidences of subsequent infection caused by ESBL-producing EC/KP versus other bacterial subsequent infection were similar (22 vs 18; P = .428). Factors associated with subsequent infection caused by ESBL-producing EC/KP include history of ESBL-producing index culture, time ≤180 days between index culture and subsequent infection, male sex, and Charlson comorbidity index score >3.
Conclusions:History of ESBL-producing EC/KP culture is associated with subsequent infection caused by ESBL-producing EC/KP, particularly within 180 days after the historical culture. Among patients presenting with infection and a history of ESBL-producing EC/KP, other factors should be considered in making empiric antibiotic decisions, and ESBL-targeted therapy may not always be warranted.
Evaluating automated electronic case report form data entry from electronic health records
- Alex C. Cheng, Mary K. Banasiewicz, Jakea D. Johnson, Lina Sulieman, Nan Kennedy, Francesco Delacqua, Adam A. Lewis, Meghan M. Joly, Amanda J. Bistran-Hall, Sean Collins, Wesley H. Self, Matthew S. Shotwell, Christopher J. Lindsell, Paul A. Harris
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- Journal:
- Journal of Clinical and Translational Science / Volume 7 / Issue 1 / 2023
- Published online by Cambridge University Press:
- 14 December 2022, e29
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Background:
Many clinical trials leverage real-world data. Typically, these data are manually abstracted from electronic health records (EHRs) and entered into electronic case report forms (CRFs), a time and labor-intensive process that is also error-prone and may miss information. Automated transfer of data from EHRs to eCRFs has the potential to reduce data abstraction and entry burden as well as improve data quality and safety.
Methods:We conducted a test of automated EHR-to-CRF data transfer for 40 participants in a clinical trial of hospitalized COVID-19 patients. We determined which coordinator-entered data could be automated from the EHR (coverage), and the frequency with which the values from the automated EHR feed and values entered by study personnel for the actual study matched exactly (concordance).
Results:The automated EHR feed populated 10,081/11,952 (84%) coordinator-completed values. For fields where both the automation and study personnel provided data, the values matched exactly 89% of the time. Highest concordance was for daily lab results (94%), which also required the most personnel resources (30 minutes per participant). In a detailed analysis of 196 instances where personnel and automation entered values differed, both a study coordinator and a data analyst agreed that 152 (78%) instances were a result of data entry error.
Conclusions:An automated EHR feed has the potential to significantly decrease study personnel effort while improving the accuracy of CRF data.
A comparison of active versus passive methods of responding to rapid diagnostic blood culture results
- Elisabeth L. Chandler, Katie L. Wallace, Elizabeth Palavecino, James R. Beardsley, James W. Johnson, Vera Luther, Christopher Ohl, John C. Williamson
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- Journal:
- Antimicrobial Stewardship & Healthcare Epidemiology / Volume 2 / Issue 1 / 2022
- Published online by Cambridge University Press:
- 02 May 2022, e75
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Objective:
To compare 2 methods of communicating polymerase chain reaction (PCR) blood-culture results: active approach utilizing on-call personnel versus passive approach utilizing notifications in the electronic health record (EHR).
Design:Retrospective observational study.
Setting:A tertiary-care academic medical center.
Patients:Adult patients hospitalized with ≥1 positive blood culture containing a gram-positive organism identified by PCR between October 2014 and January 2018.
Methods:The standard protocol for reporting PCR results at baseline included a laboratory technician calling the patient’s nurse, who would report the critical result to the medical provider. The active intervention group consisted of an on-call pager system utilizing trained pharmacy residents, whereas the passive intervention group combined standard protocol with real-time in-basket notifications to pharmacists in the EHR.
Results:Of 209 patients, 105, 61, and 43 patients were in the control, active, and passive groups, respectively. Median time to optimal therapy was shorter in the active group compared to the passive group and control (23.4 hours vs 42.2 hours vs 45.9 hours, respectively; P = .028). De-escalation occurred 12 hours sooner in the active group. In the contaminant group, empiric antibiotics were discontinued faster in the active group (0 hours) than in the control group and the passive group (17.7 vs 7.2 hours; P = .007). Time to active therapy and days of therapy were similar.
Conclusions:A passive, electronic method of reporting PCR results to pharmacists was not as effective in optimizing stewardship metrics as an active, real-time method utilizing pharmacy residents. Further studies are needed to determine the optimal method of communicating time-sensitive information.
A data mining approach to investigate food groups related to incidence of bladder cancer in the BLadder cancer Epidemiology and Nutritional Determinants International Study
- Evan Y. W. Yu, Anke Wesselius, Christoph Sinhart, Alicja Wolk, Mariana Carla Stern, Xuejuan Jiang, Li Tang, James Marshall, Eliane Kellen, Piet van den Brandt, Chih-Ming Lu, Hermann Pohlabeln, Gunnar Steineck, Mohamed Farouk Allam, Margaret R. Karagas, Carlo La Vecchia, Stefano Porru, Angela Carta, Klaus Golka, Kenneth C. Johnson, Simone Benhamou, Zuo-Feng Zhang, Cristina Bosetti, Jack A. Taylor, Elisabete Weiderpass, Eric J. Grant, Emily White, Jerry Polesel, Maurice P. A. Zeegers
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- Journal:
- British Journal of Nutrition / Volume 124 / Issue 6 / 28 September 2020
- Published online by Cambridge University Press:
- 23 April 2020, pp. 611-619
- Print publication:
- 28 September 2020
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At present, analysis of diet and bladder cancer (BC) is mostly based on the intake of individual foods. The examination of food combinations provides a scope to deal with the complexity and unpredictability of the diet and aims to overcome the limitations of the study of nutrients and foods in isolation. This article aims to demonstrate the usability of supervised data mining methods to extract the food groups related to BC. In order to derive key food groups associated with BC risk, we applied the data mining technique C5.0 with 10-fold cross-validation in the BLadder cancer Epidemiology and Nutritional Determinants study, including data from eighteen case–control and one nested case–cohort study, compromising 8320 BC cases out of 31 551 participants. Dietary data, on the eleven main food groups of the Eurocode 2 Core classification codebook, and relevant non-diet data (i.e. sex, age and smoking status) were available. Primarily, five key food groups were extracted; in order of importance, beverages (non-milk); grains and grain products; vegetables and vegetable products; fats, oils and their products; meats and meat products were associated with BC risk. Since these food groups are corresponded with previously proposed BC-related dietary factors, data mining seems to be a promising technique in the field of nutritional epidemiology and deserves further examination.
Consultation and Surgical Wait Times in Cervical Spondylotic Myelopathy
- Babak Sharifi, Greg McIntosh, Charles Fisher, W. Bradley Jacobs, Michael Johnson, Christopher S. Bailey, Sean Christie, Raphaële Charest-Morin, Jérome Paquet, Andrew Nataraj, David Cadotte, Neil Manson, Hamilton Hall, Kenneth C. Thomas, Y. Raja Rampersaud, Nicolas Dea
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- Journal:
- Canadian Journal of Neurological Sciences / Volume 46 / Issue 4 / July 2019
- Published online by Cambridge University Press:
- 03 May 2019, pp. 430-435
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Background: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord impairment. In a public healthcare system, wait times to see spine specialists and eventually access surgical treatment for CSM can be substantial. The goals of this study were to determine consultation wait times (CWT) and surgical wait times (SWT), and identify predictors of wait time length. Methods: Consecutive patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) prospective and observational CSM study from March 2015 to July 2017 were included. A data-splitting technique was used to develop and internally validate multivariable models of potential predictors. Results: A CSORN query returned 264 CSM patients for CWT. The median was 46 days. There were 31% mild, 35% moderate, and 33% severe CSM. There was a statistically significant difference in median CWT between moderate and severe groups; 207 patients underwent surgical treatment. Median SWT was 42 days. There was a statistically significant difference in SWT between mild/moderate and severe groups. Short symptom duration, less pain, lower BMI, and lower physical component score of SF-12 were predictive of shorter CWT. Only baseline pain and medication duration were predictive of SWT. Both CWT and SWT were shorter compared to a concurrent cohort of lumbar stenosis patients (p <0.001). Conclusions: Patients with shorter duration (either symptoms or medication) and less neck pain waited less to see a spine specialist in Canada and to undergo surgical treatment. This study highlights some of the obstacles to overcome in expedited care for this patient population.
Longitudinal Assessment of Self- and Informant-Subjective Cognitive Complaints in a Sample of Healthy Late-Middle Aged Adults Enriched with a Family History of Alzheimer’s Disease
- Christopher R. Nicholas, N. Maritza Dowling, Annie M. Racine, Lindsay R. Clark, Sara E. Berman, Rebecca L. Koscik, Sanjay Asthana, Bruce Hermann, Mark A. Sager, Sterling C. Johnson
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- Journal of the International Neuropsychological Society / Volume 23 / Issue 8 / September 2017
- Published online by Cambridge University Press:
- 11 July 2017, pp. 617-626
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Objectives: The purpose of this study was to investigate the longitudinal trajectory of self- and informant-subjective cognitive complaints (SCC), and to determine if SCC predict longitudinal changes in objective measures (OM) of cognitive function. Methods: The study included healthy and cognitively normal late middle-aged adults enriched with a family history of AD who were evaluated at up to three visits over a 4-year period. At each visit (Visit 1–3), self- and informant-SCC and OM were evaluated. Linear mixed models were used to determine if the longitudinal rate of change of self- and informant-SCC were associated with demographic variables, depressive symptoms, family history (FH), and apolipoprotein epsilon 4 (APOE4) status. The same modeling approach was used to examine the effect of Visit 1 SCC on longitudinal cognitive change after controlling for the same variables. Results: At Visit 1, more self-SCC were associated with fewer years of education and more depressive symptoms. SCC were also associated with poorer performance on cognitive measures, such that more self-SCC at Visit 1 were associated with poorer performance on memory and executive functioning measures at Visit 1, while more informant-SCC were associated with faster rate of longitudinal decline on a measure of episodic learning and memory. FH and APOE4 status were not associated with SCC. Discussion: Self- and informant-SCC showed an association with OM, albeit over different time frames in our late middle-aged sample. Additional longitudinal follow-up will likely assist in further clarifying these relationships as our sample ages and more pronounced cognitive changes eventually emerge. (JINS, 2017, 23, 617–626)
Dioscorea oppositifolia L. Phenotypic Evaluations and Comparison of Control Strategies
- Thomas C. Mueller, Darren K. Robinson, Joseph E. Beeler, Christopher L. Main, Dana Soehn, Kristine Johnson
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- Weed Technology / Volume 17 / Issue 4 / December 2003
- Published online by Cambridge University Press:
- 20 January 2017, pp. 705-710
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Dioscorea oppositifolia (Chinese yam) is an exotic perennial vine invading natural areas in the temperate regions of the eastern United States. Rapid early-season growth of D. oppositifolia is facilitated by an extensive tuber system. Plants can reach heights greater than 370 cm, as the plants climb trees and other vegetation. Shoot length increased 3.6 cm/d from late May to mid-August under field conditions, and primary and secondary tuber length increased 0.28 and 0.2 cm/d, respectively. This indicated rapid vegetative growth and substantial food reserves to form new plants in subsequent years. Dioscorea oppositifolia plants also formed aerial bulbils of 0.8- to 1.2-cm diameter, which are important in dissemination of the species over geographical areas. A field study indicated incomplete control from manual removal, clipping by hand, or glyphosate (2% v/v) application to control D. oppositifolia, although glyphosate was the most effective. Additionally, the use of herbicides was more efficient from a time-utilization perspective than either manual removal or clipping. In a separate study, glyphosate application at flowering was more effective in reducing D. oppositifolia growth the year after application as compared with glyphosate applications soon after emergence. Under greenhouse conditions, however, glyphosate at 0.84 kg ae/ha provided <15% control. The ester formulation of triclopyr at 2.5 kg ai/ha provided >90% D. oppositifolia control. Metsulfuron provided 31% control, and mesotrione provided 36% control and at higher rates may reduce D. oppositifolia growth. Several other herbicides having diverse modes of action provided minimal control of D. oppositifolia.
Fossil leaf economics quantified: calibration, Eocene case study, and implications
- Dana L. Royer, Lawren Sack, Peter Wilf, Bárbara Cariglino, Christopher H. Lusk, Ian J. Wright, Mark Westoby, Gregory J. Jordan, Ülo Niinemets, Phyllis D. Coley, Asher D. Cutter, Conrad C. Labandeira, Matthew B. Palmer, Kirk R. Johnson, Angela T. Moles, Fernando Valladares
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- Paleobiology / Volume 33 / Issue 4 / Fall 2007
- Published online by Cambridge University Press:
- 08 April 2016, pp. 574-589
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Leaf mass per area (MA) is a central ecological trait that is intercorrelated with leaf life span, photosynthetic rate, nutrient concentration, and palatability to herbivores. These coordinated variables form a globally convergent leaf economics spectrum, which represents a general continuum running from rapid resource acquisition to maximized resource retention. Leaf economics are little studied in ancient ecosystems because they cannot be directly measured from leaf fossils. Here we use a large extant data set (65 sites; 667 species-site pairs) to develop a new, easily measured scaling relationship between petiole width and leaf mass, normalized for leaf area; this enables MA estimation for fossil leaves from petiole width and leaf area, two variables that are commonly measurable in leaf compression floras. The calibration data are restricted to woody angiosperms exclusive of monocots, but a preliminary data set (25 species) suggests that broad-leaved gymnosperms exhibit a similar scaling. Application to two well-studied, classic Eocene floras demonstrates that MA can be quantified in fossil assemblages. First, our results are consistent with predictions from paleobotanical and paleoclimatic studies of these floras. We found exclusively low-MA species from Republic (Washington, U.S.A., 49 Ma), a humid, warm-temperate flora with a strong deciduous component among the angiosperms, and a wide MA range in a seasonally dry, warm-temperate flora from the Green River Formation at Bonanza (Utah, U.S.A., 47 Ma), presumed to comprise a mix of short and long leaf life spans. Second, reconstructed MA in the fossil species is negatively correlated with levels of insect herbivory, whether measured as the proportion of leaves with insect damage, the proportion of leaf area removed by herbivores, or the diversity of insect-damage morphotypes. These correlations are consistent with herbivory observations in extant floras and they reflect fundamental trade-offs in plant-herbivore associations. Our results indicate that several key aspects of plant and plant-animal ecology can now be quantified in the fossil record and demonstrate that herbivory has helped shape the evolution of leaf structure for millions of years.
The UCLA study of Predictors of Cognitive Functioning Following Moderate/Severe Pediatric Traumatic Brain Injury
- Lisa M. Moran, Talin Babikian, Larissa Del Piero, Monica U. Ellis, Claudia L. Kernan, Nina Newman, Christopher C. Giza, Richard Mink, Jeffrey Johnson, Christopher Babbitt, Robert Asarnow
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- Journal of the International Neuropsychological Society / Volume 22 / Issue 5 / May 2016
- Published online by Cambridge University Press:
- 28 March 2016, pp. 512-519
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Objectives: Following pediatric moderate-to-severe traumatic brain injury (msTBI), few predictors have been identified that can reliably identify which individuals are at risk for long-term cognitive difficulties. This study sought to determine the relative contribution of detailed descriptors of injury severity as well as demographic and psychosocial factors to long-term cognitive outcomes after pediatric msTBI. Methods: Participants included 8- to 19-year-olds, 46 with msTBI and 53 uninjured healthy controls (HC). Assessments were conducted in the post-acute and chronic stages of recovery. Medical record review provided details regarding acute injury severity. Parents also completed a measure of premorbid functioning and behavioral problems. The outcome of interest was four neurocognitive measures sensitive to msTBI combined to create an index of cognitive performance. Results: Results indicated that none of the detailed descriptors of acute injury severity predicted cognitive performance. Only the occurrence of injury, parental education, and premorbid academic competence predicted post-acute cognitive functioning. Long-term cognitive outcomes were best predicted by post-acute cognitive functioning. Discussion: The findings suggest that premorbid factors influence cognitive outcomes nearly as much as the occurrence of a msTBI. Furthermore, of youth with msTBI who initially recover to a level of moderate disability or better, a brief cognitive battery administered within several months after injury can best predict which individuals will experience poor long-term cognitive outcomes and require additional services. (JINS, 2016, 22, 1–8)
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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Modelling intrusions through quiescent and moving ambients
- Christopher G. Johnson, Andrew J. Hogg, Herbert E. Huppert, R. Stephen J. Sparks, Jeremy C. Phillips, Anja C. Slim, Mark J. Woodhouse
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- Journal of Fluid Mechanics / Volume 771 / 25 May 2015
- Published online by Cambridge University Press:
- 20 April 2015, pp. 370-406
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Volcanic eruptions commonly produce buoyant ash-laden plumes that rise through the stratified atmosphere. On reaching their level of neutral buoyancy, these plumes cease rising and transition to horizontally spreading intrusions. Such intrusions occur widely in density-stratified fluid environments, and in this paper we develop a shallow-layer model that governs their motion. We couple this dynamical model to a model for particle transport and sedimentation, to predict both the time-dependent distribution of ash within volcanic intrusions and the flux of ash that falls towards the ground. In an otherwise quiescent atmosphere, the intrusions spread axisymmetrically. We find that the buoyancy-inertial scalings previously identified for continuously supplied axisymmetric intrusions are not realised by solutions of the governing equations. By calculating asymptotic solutions to our model we show that the flow is not self-similar, but is instead time-dependent only in a narrow region at the front of the intrusion. This non-self-similar behaviour results in the radius of the intrusion growing with time $t$ as $t^{3/4}$, rather than $t^{2/3}$ as suggested previously. We also identify a transition to drag-dominated flow, which is described by a similarity solution with radial growth now proportional to $t^{5/9}$. In the presence of an ambient wind, intrusions are not axisymmetric. Instead, they are predominantly advected downstream, while at the same time spreading laterally and thinning vertically due to persistent buoyancy forces. We show that close to the source, this lateral spreading is in a buoyancy-inertial regime, whereas far downwind, the horizontal buoyancy forces that drive the spreading are balanced by drag. Our results emphasise the important role of buoyancy-driven spreading, even at large distances from the source, in the formation of the flowing thin horizontally extensive layers of ash that form in the atmosphere as a result of volcanic eruptions.
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- By Cecil S. Ash, Paul Barach, Ulrike Buehner, M. Ross Bullock, Leonardo Canale, Henry G. Chou, Jeffrey A. Claridge, John J. Como, Armagan Dagal, Martin Dauber, James S. Davis, Shalini Dhir, François Donati, Roman Dudaryk, Richard P. Dutton, Talmage D. Egan, Yashar Eshraghi, John R. Fisgus, Jeff Gadsden, Sugantha Ganapathy, Mark A. Gerhardt, Inderjit Gill, Joseph F. Golob, Glenn P. Gravlee, Marcello Guglielmi, Jana Hambley, Peter Hebbard, Elena J. Holak, Khadil Hosein, Ken Johnson, Matthew A. Joy, George W. Kanellakos, Olga Kaslow, Arthur M. Lam, Vanetta Levesque, Jessica Anne Lovich-Sapola, M. Jocelyn Loy, Peter F. Mahoney, Donn Marciniak, Maureen McCunn, Craig C. McFarland, Maroun J. Mhanna, Timothy Moore, Cynthia Nguyen, Maxim Novikov, E. Orestes O’Brien, Ketan P. Parekh, Claire L. Park, Michael J. A. Parr, Elie Rizkala, Steven Roth, Alistair Royse, Colin Royse, Kasia Petelenz Rubin, David Ryan, Claire Sandstrom, Carl I. Schulman, Rishad Shaikh, Ranjita Sharma, Jeffrey H. Silverstein, Peter Slinger, Charles E. Smith, Christopher Smith, Paul Soeding, Rakesh V. Sondekoppam, P. David Soran, Eldar Søreide, Elizabeth A. Steele, Kristian Strand, Dennis M. Super, Kutaiba Tabbaa, Nicholas T. Tarmey, Joshua M. Tobin, Kalpana Tyagaraj, Heather A. Vallier, Sandra Werner, Earl Willis Weyers, William C. Wilson, Shoji Yokobori, Charles J. Yowler
- Edited by Charles E. Smith
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- Book:
- Trauma Anesthesia
- Published online:
- 05 April 2015
- Print publication:
- 09 April 2015, pp vii-x
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- By Tod C. Aeby, Melanie D. Altizer, Ronan A. Bakker, Meghann E. Batten, Anita K. Blanchard, Brian Bond, Megan A. Brady, Saweda A. Bright, Ellen L. Brock, Amy Brown, Ashley Carroll, Jori S. Carter, Frances Casey, Weldon Chafe, David Chelmow, Jessica M. Ciaburri, Stephen A. Cohen, Adrianne M. Colton, PonJola Coney, Jennifer A. Cross, Julie Zemaitis DeCesare, Layson L. Denney, Megan L. Evans, Nicole S. Fanning, Tanaz R. Ferzandi, Katie P. Friday, Nancy D. Gaba, Rajiv B. Gala, Andrew Galffy, Adrienne L. Gentry, Edward J. Gill, Philippe Girerd, Meredith Gray, Amy Hempel, Audra Jolyn Hill, Chris J. Hong, Kathryn A. Houston, Patricia S. Huguelet, Warner K. Huh, Jordan Hylton, Christine R. Isaacs, Alison F. Jacoby, Isaiah M. Johnson, Nicole W. Karjane, Emily E. Landers, Susan M. Lanni, Eduardo Lara-Torre, Lee A. Learman, Nikola Alexander Letham, Rachel K. Love, Richard Scott Lucidi, Elisabeth McGaw, Kimberly Woods McMorrow, Christopher A. Manipula, Kirk J. Matthews, Michelle Meglin, Megan Metcalf, Sarah H. Milton, Gaby Moawad, Christopher Morosky, Lindsay H. Morrell, Elizabeth L. Munter, Erin L. Murata, Amanda B. Murchison, Nguyet A. Nguyen, Nan G. O’Connell, Tony Ogburn, K. Nathan Parthasarathy, Thomas C. Peng, Ashley Peterson, Sarah Peterson, John G. Pierce, Amber Price, Heidi J. Purcell, Ronald M. Ramus, Nicole Calloway Rankins, Fidelma B. Rigby, Amanda H. Ritter, Barbara L. Robinson, Danielle Roncari, Lisa Rubinsak, Jennifer Salcedo, Mary T. Sale, Peter F. Schnatz, John W. Seeds, Kathryn Shaia, Karen Shelton, Megan M. Shine, Haller J. Smith, Roger P. Smith, Nancy A. Sokkary, Reni A. Soon, Aparna Sridhar, Lilja Stefansson, Laurie S. Swaim, Chemen M. Tate, Hong-Thao Thieu, Meredith S. Thomas, L. Chesney Thompson, Tiffany Tonismae, Angela M. Tran, Breanna Walker, Alan G. Waxman, C. Nathan Webb, Valerie L. Williams, Sarah B. Wilson, Elizabeth M. Yoselevsky, Amy E. Young
- Edited by David Chelmow, Virginia Commonwealth University, Christine R. Isaacs, Virginia Commonwealth University, Ashley Carroll, Virginia Commonwealth University
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- Book:
- Acute Care and Emergency Gynecology
- Published online:
- 05 November 2014
- Print publication:
- 30 October 2014, pp ix-xiv
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- By Ainsworth Shaaron, Ayres Paul, Azevedo Roger, Bediou Benoit, Britt Anne, Kirsten R. Butcher, Chen Fei, Michelene T. H. Chi, Richard E. Clark, Ruth Colvin Clark, Sharon J. Derry, David F. Feldon, Fiorella Logan, J. D. Fletcher, Arthur C. Graesser, Hegarty Mary, HU Xiangen, Allison J. Jaeger, Janssen Jeroen, Cheryl I. Johnson, Ton De Jong, Kalyuga Slava, Kester Liesbeth, Kirschner Femke, Paul A. Kirschner, Susanne P. Lajoie, Ard W. Lazonder, Leutner Detlev, Low Renae, Richard K. Lowe, Richard E. Mayer, Benjamin D. Nye, Paas Fred, Pilegard Celeste, Jan L. Plass, Heather A. Priest, Renkl Alexander, Rouet Jean-FranÇois, Christopher A. Sanchez, Scheiter Katharina, Schmeck Annett, Schnotz Wolfgang, Ruth N. Schwartz, Bruce L. Sherin, Miriam Gamoran Sherin, Sweller John, Tobias Sigmund, Tamara Van Gog, Jeroen J. G. Van MerriËNboer, Jennifer Wiley, Alexander P. Wind, Ruth Wylie
- Edited by Richard E. Mayer, University of California, Santa Barbara
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- Book:
- The Cambridge Handbook of Multimedia Learning
- Published online:
- 05 August 2014
- Print publication:
- 28 July 2014, pp ix-x
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Bivalve Mollusk Assemblage of Bed III, Olduvai Gorge, Tanzania
- Claudia C. Johnson, Jackson K. Njau, Christopher E. Kauffman, Erle G. Kauffman, Nicholas P. Toth, Kathy Schick, John Kearney
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- Journal:
- The Paleontological Society Special Publications / Volume 13 / 2014
- Published online by Cambridge University Press:
- 26 July 2017, pp. 35-36
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- 2014
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- By Lassi Alvesalo, Alberto Anta, Juan Luis Arsuaga, Shara E. Bailey, Priscilla Bayle, José María Bermúdez de Castro, Tracy K. Betsinger, Luca Bondioli, Scott E. Burnett, Concepcion de la Rúa, William N. Duncan, Ryan M. Durner, Heather J.H. Edgar, Scott M. Fitzpatrick, Michael R. Fong, Ana Gracia-Téllez, Theresa M. Grieco, Debbie Guatelli-Steinberg, Tsunehiko Hanihara, Brian E. Hemphill, Leslea J. Hlusko, Michael W. Holmes, Jean-Jacques Hublin, Toby E. Hughes, John P. Hunter, Joel D. Irish, Kent M. Johnson, Sri Kuswandari, Christine Lee, John R. Lukacs, Roberto Macchiarelli, Laura Martín-Francés, Ignacio Martínez, María Martinón-Torres, Arnaud Mazurier, Yuji Mizoguchi, Stephanie Moormann, Greg C. Nelson, Stephen D. Ousley, Oliver T. Rizk, G. Richard Scott, Roman Schomberg, Kes Schroer, Christopher M. Stojanowski, Grant C. Townsend, Christy G. Turner, Theresia C. Weston, Bernard Wood, Clément Zanolli, Linhu Zhang
- Edited by G. Richard Scott, University of Alaska, Fairbanks, Joel D. Irish, Liverpool John Moores University
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- Book:
- Anthropological Perspectives on Tooth Morphology
- Published online:
- 05 March 2013
- Print publication:
- 21 February 2013, pp viii-xi
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- By Jeffrey Anderson, Sabrina Bent, Lesley Bourlet, Ann Bui, Seth Christian, Ashish Dabas, Judy Dahle, Franklin Dexter, Richard P. Dutton, Christoph Egger, Richard H. Epstein, Deborah Farmer, Charles J. Fox, Melissa Guidry, Barbara Harris, Michael R. Hicks, Judy G. Johnson, Zeev Kain, Alicia G. Kalamas, Alan D. Kaye, Valeriy Kozmenko, Henry Liu, Asa C. Lockhart, Robert Lynch, Alex Macario, Dipty Mangla, Ross Musumeci, George Mychaskiw, Frank G. Opelka, Pat Patterson, Sonya Pease, Nigel N. Robertson, Frank Rosinia, Keith J. Ruskin, Laurie Saletnik, Devona Slater, Bernadine Smith, Richard D. Urman, Shermeen B. Vakharia, Steven D. Waldman, John J. Wellik, Michael R. Williams, Melville Wyche, Michael J. Yarborough
- Edited by Alan D. Kaye, Louisiana State University, Charles J. Fox, III, Richard D. Urman
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- Book:
- Operating Room Leadership and Management
- Published online:
- 05 October 2012
- Print publication:
- 04 October 2012, pp ix-xi
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- By Chittima Aryuthaka, William J. Baker, Chris Banks, David R. Bellwood, David Bickford, Rafe M. Brown, Mark de Bruyn, Patrick Campbell, Charles H. Cannon, Gary R. Carvalho, Craig M. Costion, Thomas L. P. Couvreur, Ben J. Evans, Nicholas J. Evans, Matthias Glaubrecht, David J. Gower, Robert Hall, Fabian Herder, Aljosja Hooijer, Agata Hoscilo, Chawaporn Jittanoon, Kenneth G. Johnson, Michael A. Kendall, Peter B. Mather, Yaowaluk Monthum, Robert J. Morley, Alexandra N. Muellner, Vincent Nijman, Les R. Noble, Kevin M. O’Neill, Susan Page, Gordon L. J. Paterson, Sinlan Poo, Mary Rose C. Posa, Richard Ree, Willem Renema, James E. Richardson, Jack Rieley, Kristina von Rintelen, Thomas von Rintelen, Brian R. Rosen, Lukas Rüber, Christoph D. Schubart, Chris R. Shepherd, Bryan L. Stuart, Matthew Todd, Campbell O. Webb, Suzanne T. Williams, John van Wyhe
- Edited by David Gower, Natural History Museum, London, Kenneth Johnson, Natural History Museum, London, James Richardson, Royal Botanic Garden Edinburgh, Brian Rosen, Natural History Museum, London, Lukas Rüber, Suzanne Williams, Natural History Museum, London
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- Book:
- Biotic Evolution and Environmental Change in Southeast Asia
- Published online:
- 05 August 2012
- Print publication:
- 19 July 2012, pp vii-x
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- By Kumar Alagappan, Janet G. Alteveer, Kim Askew, Paul S. Auerbach, Katherine Bakes, Kip Benko, Paul D. Biddinger, Victoria Brazil, Anthony FT Brown, Andrew K. Chang, Alice Chiao, Wendy C. Coates, Jamie Collings, Gilbert Abou Dagher, Jonathan E. Davis, Peter DeBlieux, Alessandro Dellai, Emily Doelger, Pamela L. Dyne, Gino Farina, Robert Galli, Gus M. Garmel, Daniel Garza, Laleh Gharahbaghian, Gregory H. Gilbert, Michael A. Gisondi, Steven Go, Jeffrey M. Goodloe, Swaminatha V. Gurudevan, Micelle J. Haydel, Stephen R. Hayden, Corey R. Heitz, Gregory W. Hendey, Mel Herbert, Cherri Hobgood, Michelle Huston, Loretta Jackson-Williams, Anja K. Jaehne, Mary Beth Johnson, H. Brendan Kelleher, Peter G Kumasaka, Melissa J. Lamberson, Mary Lanctot-Herbert, Erik Laurin, Brian Lin, Michelle Lin, Douglas Lowery-North, Sharon E. Mace, S. V. Mahadevan, Thomas M. Mailhot, Diku Mandavia, David E. Manthey, Jorge A. Martinez, Amal Mattu, Lynne McCullough, Steve McLaughlin, Timothy Meyers, Gregory J. Moran, Randall T. Myers, Christopher R.H. Newton, Flavia Nobay, Robert L. Norris, Catherine Oliver, Jennifer A. Oman, Rita Oregon, Phillips Perera, Susan B. Promes, Emanuel P. Rivers, John S. Rose, Carolyn J. Sachs, Jairo I. Santanilla, Rawle A. Seupaul, Fred A. Severyn, Ghazala Q. Sharieff, Lee W. Shockley, Stefanie Simmons, Barry C. Simon, Shannon Sovndal, George Sternbach, Matthew Strehlow, Eustacia (Jo) Su, Stuart P. Swadron, Jeffrey A. Tabas, Sophie Terp, R. Jason Thurman, David A. Wald, Sarah R. Williams, Teresa S. Wu, Ken Zafren
- Edited by S. V. Mahadevan, Stanford University School of Medicine, California, Gus M. Garmel
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- Book:
- An Introduction to Clinical Emergency Medicine
- Published online:
- 05 May 2012
- Print publication:
- 10 April 2012, pp xi-xvi
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Show Me the Money: Long-Term Financial Impact of an Antimicrobial Stewardship Program
- James R. Beardsley, John C. Williamson, James W. Johnson, Vera P. Luther, Rebekah H. Wrenn, Christopher C. Ohl
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 33 / Issue 4 / April 2012
- Published online by Cambridge University Press:
- 02 January 2015, pp. 398-400
- Print publication:
- April 2012
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The financial impact of an antimicrobial stewardship program in operation for more than 11 years was determined by calculating the reduction in antimicrobial expenditures minus program labor costs. Depending on the method of inflation adjustment used, the program was associated with average cost savings of $920,070 to $2,064,441 per year.