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6 Adjunctive Transcranial Direct Current Stimulation and Cognitive Training Alters Default Mode and Frontoparietal Control Network Connectivity in Older Adults
- Hanna K Hausman, Jessica N Kraft, Cheshire Hardcastle, Nicole D Evangelista, Emanuel M Boutzoukas, Andrew O’Shea, Alejandro Albizu, Emily J Van Etten, Pradyumna K Bharadwaj, Hyun Song, Samantha G Smith, Eric S Porges, Georg A Hishaw, Samuel Wu, Steven DeKosky, Gene E Alexander, Michael Marsiske, Ronald A Cohen, Adam J Woods
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 675-676
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Objective:
Aging is associated with disruptions in functional connectivity within the default mode (DMN), frontoparietal control (FPCN), and cingulo-opercular (CON) resting-state networks. Greater within-network connectivity predicts better cognitive performance in older adults. Therefore, strengthening network connectivity, through targeted intervention strategies, may help prevent age-related cognitive decline or progression to dementia. Small studies have demonstrated synergistic effects of combining transcranial direct current stimulation (tDCS) and cognitive training (CT) on strengthening network connectivity; however, this association has yet to be rigorously tested on a large scale. The current study leverages longitudinal data from the first-ever Phase III clinical trial for tDCS to examine the efficacy of an adjunctive tDCS and CT intervention on modulating network connectivity in older adults.
Participants and Methods:This sample included 209 older adults (mean age = 71.6) from the Augmenting Cognitive Training in Older Adults multisite trial. Participants completed 40 hours of CT over 12 weeks, which included 8 attention, processing speed, and working memory tasks. Participants were randomized into active or sham stimulation groups, and tDCS was administered during CT daily for two weeks then weekly for 10 weeks. For both stimulation groups, two electrodes in saline-soaked 5x7 cm2 sponges were placed at F3 (cathode) and F4 (anode) using the 10-20 measurement system. The active group received 2mA of current for 20 minutes. The sham group received 2mA for 30 seconds, then no current for the remaining 20 minutes.
Participants underwent resting-state fMRI at baseline and post-intervention. CONN toolbox was used to preprocess imaging data and conduct region of interest (ROI-ROI) connectivity analyses. The Artifact Detection Toolbox, using intermediate settings, identified outlier volumes. Two participants were excluded for having greater than 50% of volumes flagged as outliers. ROI-ROI analyses modeled the interaction between tDCS group (active versus sham) and occasion (baseline connectivity versus postintervention connectivity) for the DMN, FPCN, and CON controlling for age, sex, education, site, and adherence.
Results:Compared to sham, the active group demonstrated ROI-ROI increases in functional connectivity within the DMN following intervention (left temporal to right temporal [T(202) = 2.78, pFDR < 0.05] and left temporal to right dorsal medial prefrontal cortex [T(202) = 2.74, pFDR < 0.05]. In contrast, compared to sham, the active group demonstrated ROI-ROI decreases in functional connectivity within the FPCN following intervention (left dorsal prefrontal cortex to left temporal [T(202) = -2.96, pFDR < 0.05] and left dorsal prefrontal cortex to left lateral prefrontal cortex [T(202) = -2.77, pFDR < 0.05]). There were no significant interactions detected for CON regions.
Conclusions:These findings (a) demonstrate the feasibility of modulating network connectivity using tDCS and CT and (b) provide important information regarding the pattern of connectivity changes occurring at these intervention parameters in older adults. Importantly, the active stimulation group showed increases in connectivity within the DMN (a network particularly vulnerable to aging and implicated in Alzheimer’s disease) but decreases in connectivity between left frontal and temporal FPCN regions. Future analyses from this trial will evaluate the association between these changes in connectivity and cognitive performance post-intervention and at a one-year timepoint.
9 Connecting memory and functional brain networks in older adults: a resting state fMRI study
- Jori L Waner, Hanna K Hausman, Jessica N Kraft, Cheshire Hardcastle, Nicole D Evangelista, Andrew O’Shea, Alejandro Albizu, Emanuel M Boutzoukas, Emily J Van Etten, Pradyumna K Bharadwaj, Hyun Song, Samantha G Smith, Steven T DeKosky, Georg A Hishaw, Samuel S Wu, Michael Marsiske, Ronald Cohen, Gene E Alexander, Eric C Porges, Adam J Woods
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 527-528
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Objective:
Nonpathological aging has been linked to decline in both verbal and visuospatial memory abilities in older adults. Disruptions in resting-state functional connectivity within well-characterized, higherorder cognitive brain networks have also been coupled with poorer memory functioning in healthy older adults and in older adults with dementia. However, there is a paucity of research on the association between higherorder functional connectivity and verbal and visuospatial memory performance in the older adult population. The current study examines the association between resting-state functional connectivity within the cingulo-opercular network (CON), frontoparietal control network (FPCN), and default mode network (DMN) and verbal and visuospatial learning and memory in a large sample of healthy older adults. We hypothesized that greater within-network CON and FPCN functional connectivity would be associated with better immediate verbal and visuospatial memory recall. Additionally, we predicted that within-network DMN functional connectivity would be associated with improvements in delayed verbal and visuospatial memory recall. This study helps to glean insight into whether within-network CON, FPCN, or DMN functional connectivity is associated with verbal and visuospatial memory abilities in later life.
Participants and Methods:330 healthy older adults between 65 and 89 years old (mean age = 71.6 ± 5.2) were recruited at the University of Florida (n = 222) and the University of Arizona (n = 108). Participants underwent resting-state fMRI and completed verbal memory (Hopkins Verbal Learning Test - Revised [HVLT-R]) and visuospatial memory (Brief Visuospatial Memory Test - Revised [BVMT-R]) measures. Immediate (total) and delayed recall scores on the HVLT-R and BVMT-R were calculated using each test manual’s scoring criteria. Learning ratios on the HVLT-R and BVMT-R were quantified by dividing the number of stimuli (verbal or visuospatial) learned between the first and third trials by the number of stimuli not recalled after the first learning trial. CONN Toolbox was used to extract average within-network connectivity values for CON, FPCN, and DMN. Hierarchical regressions were conducted, controlling for sex, race, ethnicity, years of education, number of invalid scans, and scanner site.
Results:Greater CON connectivity was significantly associated with better HVLT-R immediate (total) recall (ß = 0.16, p = 0.01), HVLT-R learning ratio (ß = 0.16, p = 0.01), BVMT-R immediate (total) recall (ß = 0.14, p = 0.02), and BVMT-R delayed recall performance (ß = 0.15, p = 0.01). Greater FPCN connectivity was associated with better BVMT-R learning ratio (ß = 0.13, p = 0.04). HVLT-R delayed recall performance was not associated with connectivity in any network, and DMN connectivity was not significantly related to any measure.
Conclusions:Connectivity within CON demonstrated a robust relationship with different components of memory function as well across verbal and visuospatial domains. In contrast, FPCN only evidenced a relationship with visuospatial learning, and DMN was not significantly associated with memory measures. These data suggest that CON may be a valuable target in longitudinal studies of age-related memory changes, but also a possible target in future non-invasive interventions to attenuate memory decline in older adults.
Meta-analysis across Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium provides evidence for an association of serum vitamin D with pulmonary function
- Jiayi Xu, Traci M. Bartz, Geetha Chittoor, Gudny Eiriksdottir, Ani W. Manichaikul, Fangui Sun, Natalie Terzikhan, Xia Zhou, Sarah L. Booth, Guy G. Brusselle, Ian H. de Boer, Myriam Fornage, Alexis C. Frazier-Wood, Mariaelisa Graff, Vilmundur Gudnason, Tamara B. Harris, Albert Hofman, Ruixue Hou, Denise K. Houston, David R. Jacobs, Jr, Stephen B. Kritchevsky, Jeanne Latourelle, Rozenn N. Lemaitre, Pamela L. Lutsey, George O’Connor, Elizabeth C. Oelsner, James S. Pankow, Bruce M. Psaty, Rebecca R. Rohde, Stephen S. Rich, Jerome I. Rotter, Lewis J. Smith, Bruno H. Stricker, V. Saroja Voruganti, Thomas J. Wang, M. Carola Zillikens, R. Graham Barr, Josée Dupuis, Sina A. Gharib, Lies Lahousse, Stephanie J. London, Kari E. North, Albert V. Smith, Lyn M. Steffen, Dana B. Hancock, Patricia A. Cassano
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- Journal:
- British Journal of Nutrition / Volume 120 / Issue 10 / 28 November 2018
- Published online by Cambridge University Press:
- 12 September 2018, pp. 1159-1170
- Print publication:
- 28 November 2018
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The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
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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 Frank Andrasik, Melissa R. Andrews, Ana Inés Ansaldo, Evangelos G. Antzoulatos, Lianhua Bai, Ellen Barrett, Linamara Battistella, Nicolas Bayle, Michael S. Beattie, Peter J. Beek, Serafin Beer, Heinrich Binder, Claire Bindschaedler, Sarah Blanton, Tasia Bobish, Michael L. Boninger, Joseph F. Bonner, Chadwick B. Boulay, Vanessa S. Boyce, Anna-Katharine Brem, Jacqueline C. Bresnahan, Floor E. Buma, Mary Bartlett Bunge, John H. Byrne, Jeffrey R. Capadona, Stefano F. Cappa, Diana D. Cardenas, Leeanne M. Carey, S. Thomas Carmichael, Glauco A. P. Caurin, Pablo Celnik, Kimberly M. Christian, Stephanie Clarke, Leonardo G. Cohen, Adriana B. Conforto, Rory A. Cooper, Rosemarie Cooper, Steven C. Cramer, Armin Curt, Mark D’Esposito, Matthew B. Dalva, Gavriel David, Brandon Delia, Wenbin Deng, Volker Dietz, Bruce H. Dobkin, Marco Domeniconi, Edith Durand, Tracey Vause Earland, Georg Ebersbach, Jonathan J. Evans, James W. Fawcett, Uri Feintuch, Toby A. Ferguson, Marie T. Filbin, Diasinou Fioravante, Itzhak Fischer, Agnes Floel, Herta Flor, Karim Fouad, Richard S. J. Frackowiak, Peter H. Gorman, Thomas W. Gould, Jean-Michel Gracies, Amparo Gutierrez, Kurt Haas, C.D. Hall, Hans-Peter Hartung, Zhigang He, Jordan Hecker, Susan J. Herdman, Seth Herman, Leigh R. Hochberg, Ahmet Höke, Fay B. Horak, Jared C. Horvath, Richard L. Huganir, Friedhelm C. Hummel, Beata Jarosiewicz, Frances E. Jensen, Michael Jöbges, Larry M. Jordan, Jon H. Kaas, Andres M. Kanner, Noomi Katz, Matthew S. Kayser, Annmarie Kelleher, Gerd Kempermann, Timothy E. Kennedy, Jürg Kesselring, Fary Khan, Rachel Kizony, Jeffery D. Kocsis, Boudewijn J. Kollen, Hubertus Köller, John W. Krakauer, Hermano I. Krebs, Gert Kwakkel, Bradley Lang, Catherine E. Lang, Helmar C. Lehmann, Angelo C. Lepore, Glenn S. Le Prell, Mindy F. Levin, Joel M. Levine, David A. Low, Marilyn MacKay-Lyons, Jeffrey D. Macklis, Margaret Mak, Francine Malouin, William C. Mann, Paul D. Marasco, Christopher J. Mathias, Laura McClure, Jan Mehrholz, Lorne M. Mendell, Robert H. Miller, Carol Milligan, Beth Mineo, Simon W. Moore, Jennifer Morgan, Charbel E-H. Moussa, Martin Munz, Randolph J. Nudo, Joseph J. Pancrazio, Theresa Pape, Alvaro Pascual-Leone, Kristin M. Pearson-Fuhrhop, P. Hunter Peckham, Tamara L. Pelleshi, Catherine Verrier Piersol, Thomas Platz, Marcus Pohl, Dejan B. Popović, Andrew M. Poulos, Maulik Purohit, Hui-Xin Qi, Debbie Rand, Mahendra S. Rao, Josef P. Rauschecker, Aimee Reiss, Carol L. Richards, Keith M. Robinson, Melvyn Roerdink, John C. Rosenbek, Serge Rossignol, Edward S. Ruthazer, Arash Sahraie, Krishnankutty Sathian, Marc H. Schieber, Brian J. Schmidt, Michael E. Selzer, Mijail D. Serruya, Himanshu Sharma, Michael Shifman, Jerry Silver, Thomas Sinkjær, George M. Smith, Young-Jin Son, Tim Spencer, John D. Steeves, Oswald Steward, Sheela Stuart, Austin J. Sumner, Chin Lik Tan, Robert W. Teasell, Gareth Thomas, Aiko K. Thompson, Richard F. Thompson, Wesley J. Thompson, Erika Timar, Ceri T. Trevethan, Christopher Trimby, Gary R. Turner, Mark H. Tuszynski, Erna A. van Niekerk, Ricardo Viana, Difei Wang, Anthony B. Ward, Nick S. Ward, Stephen G. Waxman, Patrice L. Weiss, Jörg Wissel, Steven L. Wolf, Jonathan R. Wolpaw, Sharon Wood-Dauphinee, Ross D. Zafonte, Binhai Zheng, Richard D. Zorowitz
- Edited by Michael Selzer, Stephanie Clarke, Leonardo Cohen, Gert Kwakkel, Robert Miller, Case Western Reserve University, Ohio
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- Textbook of Neural Repair and Rehabilitation
- Published online:
- 05 May 2014
- Print publication:
- 24 April 2014, pp ix-xvi
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- By Frank Andrasik, Melissa R. Andrews, Ana Inés Ansaldo, Evangelos G. Antzoulatos, Lianhua Bai, Ellen Barrett, Linamara Battistella, Nicolas Bayle, Michael S. Beattie, Peter J. Beek, Serafin Beer, Heinrich Binder, Claire Bindschaedler, Sarah Blanton, Tasia Bobish, Michael L. Boninger, Joseph F. Bonner, Chadwick B. Boulay, Vanessa S. Boyce, Anna-Katharine Brem, Jacqueline C. Bresnahan, Floor E. Buma, Mary Bartlett Bunge, John H. Byrne, Jeffrey R. Capadona, Stefano F. Cappa, Diana D. Cardenas, Leeanne M. Carey, S. Thomas Carmichael, Glauco A. P. Caurin, Pablo Celnik, Kimberly M. Christian, Stephanie Clarke, Leonardo G. Cohen, Adriana B. Conforto, Rory A. Cooper, Rosemarie Cooper, Steven C. Cramer, Armin Curt, Mark D’Esposito, Matthew B. Dalva, Gavriel David, Brandon Delia, Wenbin Deng, Volker Dietz, Bruce H. Dobkin, Marco Domeniconi, Edith Durand, Tracey Vause Earland, Georg Ebersbach, Jonathan J. Evans, James W. Fawcett, Uri Feintuch, Toby A. Ferguson, Marie T. Filbin, Diasinou Fioravante, Itzhak Fischer, Agnes Floel, Herta Flor, Karim Fouad, Richard S. J. Frackowiak, Peter H. Gorman, Thomas W. Gould, Jean-Michel Gracies, Amparo Gutierrez, Kurt Haas, C.D. Hall, Hans-Peter Hartung, Zhigang He, Jordan Hecker, Susan J. Herdman, Seth Herman, Leigh R. Hochberg, Ahmet Höke, Fay B. Horak, Jared C. Horvath, Richard L. Huganir, Friedhelm C. Hummel, Beata Jarosiewicz, Frances E. Jensen, Michael Jöbges, Larry M. Jordan, Jon H. Kaas, Andres M. Kanner, Noomi Katz, Matthew S. Kayser, Annmarie Kelleher, Gerd Kempermann, Timothy E. Kennedy, Jürg Kesselring, Fary Khan, Rachel Kizony, Jeffery D. Kocsis, Boudewijn J. Kollen, Hubertus Köller, John W. Krakauer, Hermano I. Krebs, Gert Kwakkel, Bradley Lang, Catherine E. Lang, Helmar C. Lehmann, Angelo C. Lepore, Glenn S. Le Prell, Mindy F. Levin, Joel M. Levine, David A. Low, Marilyn MacKay-Lyons, Jeffrey D. Macklis, Margaret Mak, Francine Malouin, William C. Mann, Paul D. Marasco, Christopher J. Mathias, Laura McClure, Jan Mehrholz, Lorne M. Mendell, Robert H. Miller, Carol Milligan, Beth Mineo, Simon W. Moore, Jennifer Morgan, Charbel E-H. Moussa, Martin Munz, Randolph J. Nudo, Joseph J. Pancrazio, Theresa Pape, Alvaro Pascual-Leone, Kristin M. Pearson-Fuhrhop, P. Hunter Peckham, Tamara L. Pelleshi, Catherine Verrier Piersol, Thomas Platz, Marcus Pohl, Dejan B. Popović, Andrew M. Poulos, Maulik Purohit, Hui-Xin Qi, Debbie Rand, Mahendra S. Rao, Josef P. Rauschecker, Aimee Reiss, Carol L. Richards, Keith M. Robinson, Melvyn Roerdink, John C. Rosenbek, Serge Rossignol, Edward S. Ruthazer, Arash Sahraie, Krishnankutty Sathian, Marc H. Schieber, Brian J. Schmidt, Michael E. Selzer, Mijail D. Serruya, Himanshu Sharma, Michael Shifman, Jerry Silver, Thomas Sinkjær, George M. Smith, Young-Jin Son, Tim Spencer, John D. Steeves, Oswald Steward, Sheela Stuart, Austin J. Sumner, Chin Lik Tan, Robert W. Teasell, Gareth Thomas, Aiko K. Thompson, Richard F. Thompson, Wesley J. Thompson, Erika Timar, Ceri T. Trevethan, Christopher Trimby, Gary R. Turner, Mark H. Tuszynski, Erna A. van Niekerk, Ricardo Viana, Difei Wang, Anthony B. Ward, Nick S. Ward, Stephen G. Waxman, Patrice L. Weiss, Jörg Wissel, Steven L. Wolf, Jonathan R. Wolpaw, Sharon Wood-Dauphinee, Ross D. Zafonte, Binhai Zheng, Richard D. Zorowitz
- Edited by Michael E. Selzer, Stephanie Clarke, Leonardo G. Cohen, Gert Kwakkel, Robert H. Miller, Case Western Reserve University, Ohio
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- Textbook of Neural Repair and Rehabilitation
- Published online:
- 05 June 2014
- Print publication:
- 24 April 2014, pp ix-xvi
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- By Ghazi Al-Rawas, Vazken Andréassian, Tianqi Ao, Stacey A. Archfield, Berit Arheimer, András Bárdossy, Trent Biggs, Günter Blöschl, Theresa Blume, Marco Borga, Helge Bormann, Gianluca Botter, Tom Brown, Donald H. Burn, Sean K. Carey, Attilio Castellarin, Francis Chiew, François Colin, Paulin Coulibaly, Armand Crabit, Barry Croke, Siegfried Demuth, Qingyun Duan, Giuliano Di Baldassarre, Thomas Dunne, Ying Fan, Xing Fang, Boris Gartsman, Alexander Gelfan, Mikhail Georgievski, Nick van de Giesen, David C. Goodrich, Hoshin V. Gupta, Khaled Haddad, David M. Hannah, H. A. P. Hapuarachchi, Hege Hisdal, Kamila Hlavčová, Markus Hrachowitz, Denis A. Hughes, Günter Humer, Ruud Hurkmans, Vito Iacobellis, Elena Ilyichyova, Hiroshi Ishidaira, Graham Jewitt, Shaofeng Jia, Jeffrey R. Kennedy, Anthony S. Kiem, Robert Kirnbauer, Thomas R. Kjeldsen, Jürgen Komma, Leonid M. Korytny, Charles N. Kroll, George Kuczera, Gregor Laaha, Henny A. J. van Lanen, Hjalmar Laudon, Jens Liebe, Shijun Lin, Göran Lindström, Suxia Liu, Jun Magome, Danny G. Marks, Dominic Mazvimavi, Jeffrey J. McDonnell, Brian L. McGlynn, Kevin J. McGuire, Neil McIntyre, Thomas A. McMahon, Ralf Merz, Robert A. Metcalfe, Alberto Montanari, David Morris, Roger Moussa, Lakshman Nandagiri, Thomas Nester, Taha B. M. J. Ouarda, Ludovic Oudin, Juraj Parajka, Charles S. Pearson, Murray C. Peel, Charles Perrin, John W. Pomeroy, David A. Post, Ataur Rahman, Liliang Ren, Magdalena Rogger, Dan Rosbjerg, José Luis Salinas, Jos Samuel, Eric Sauquet, Hubert H. G. Savenije, Takahiro Sayama, John C. Schaake, Kevin Shook, Murugesu Sivapalan, Jon Olav Skøien, Chris Soulsby, Christopher Spence, R. ‘Sri’ Srikanthan, Tammo S. Steenhuis, Jan Szolgay, Yasuto Tachikawa, Kuniyoshi Takeuchi, Lena M. Tallaksen, Dörthe Tetzlaff, Sally E. Thompson, Elena Toth, Peter A. Troch, Remko Uijlenhoet, Carl L. Unkrich, Alberto Viglione, Neil R. Viney, Richard M. Vogel, Thorsten Wagener, M. Todd Walter, Guoqiang Wang, Markus Weiler, Rolf Weingartner, Erwin Weinmann, Hessel Winsemius, Ross A. Woods, Dawen Yang, Chihiro Yoshimura, Andy Young, Gordon Young, Erwin Zehe, Yongqiang Zhang, Maichun C. Zhou
- Edited by Günter Blöschl, Technische Universität Wien, Austria, Murugesu Sivapalan, University of Illinois, Urbana-Champaign, Thorsten Wagener, University of Bristol, Alberto Viglione, Technische Universität Wien, Austria, Hubert Savenije, Technische Universiteit Delft, The Netherlands
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- Book:
- Runoff Prediction in Ungauged Basins
- Published online:
- 05 April 2013
- Print publication:
- 18 April 2013, pp ix-xiv
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- By Krista Adamek, Ana Luisa K. Albernaz, J. Marcio Ayres†, Andrew J. Baker, Karen L. Bales, Adrian A. Barnett, Christopher Barton, John M. Bates, Jennie Becker, Bruna M. Bezerra, Júlio César Bicca-Marques, Richard Bodmer, Jean P. Boubli, Mark Bowler, Sarah A. Boyle, Christini Barbosa Caselli, Janice Chism, Elena P. Cunningham, José Maria C. da Silva, Lesa C. Davies, Nayara de Alcântara Cardoso, Manuella A. de Souza, Stella de la Torre, Ana Gabriela de Luna, Thomas R. Defler, Anthony Di Fiore, Eduardo Fernandez-Duque, Stephen F. Ferrari, Wilsea M.B. Figueiredo-Ready, Tracy Frampton, Paul A. Garber, Brian W. Grafton, L. Tremaine Gregory, Maria L. Harada, Amy Harrison-Levine, Walter C. Hartwig, Stefanie Heiduck, Eckhard W. Heymann, André Hirsch, Leandro Jerusalinsky, Gareth Jones, Richard F. Kay, Martin M. Kowalewski, Shawn M. Lehman, Laura Marsh, Jesús Martinez, William A. Mason, Hope Matthews, Wynlyn McBride, Shona McCann-Wood, W. Scott McGraw, D. Jeffrey Meldrum, Sally P. Mendoza, Nohelia Mercado, Russell A. Mittermeier, Mirjam N. Nadjafzadeh, Marilyn A. Norconk, Robert Gary Norman, Marcela Oliveira, Marcelo M. Oliveira, Maria Juliana Ospina Rodríguez, Erwin Palacios, Suzanne Palminteri, Liliam P. Pinto, Marcio Port-Carvalho, Leila Porter, Carlos Portillo-Quintero, George Powell, Ghillean T. Prance, Rodrigo C. Printes, Pablo Puertas, P. Kirsten Pullen, Helder L. Queiroz, Luis Reginaldo R. Rodrigues, Adriana Rodríguez, Alfred L. Rosenberger, Anthony B. Rylands, Ricardo R. Santos, Horacio Schneider, Eleonore Z.F. Setz, Suleima S.B. Silva, José S. Silva Júnior, Andrew T. Smith, Marcelo C. Sousa, Antonio S. Souto, Wilson R. Spironello, Masanaru Takai, Marcelo F. Tejedor, Cynthia L. Thompson, Diego G. Tirira, Raul Tupayachi, Bernardo Urbani, Liza M. Veiga, Marianela Velilla, João Valsecchi, Jean-Christophe Vié, Tatiana M. Vieira, Suzanne E. Walker-Pacheco, Rob Wallace, Patricia C. Wright, Charles E. Zartman
- Edited by Liza M. Veiga, Universidade Federal do Pará, Brazil, Adrian A. Barnett, Roehampton University, London, Stephen F. Ferrari, Universidade Federal de Sergipe, Brazil, Marilyn A. Norconk, Kent State University, Ohio
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- Book:
- Evolutionary Biology and Conservation of Titis, Sakis and Uacaris
- Published online:
- 05 April 2013
- Print publication:
- 11 April 2013, pp xii-xv
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- By Basem Abdelmalak, Linda S. Aglio, Daniel Alam, Maged Argalious, Carlos A. Artime, Rahul G. Baijal, David Beebe, Michael S. Benninger, Carol R. Bradford, Paul C. Bryson, Brian Burkey, Richard M. Cooper, Jacek B. Cywinski, Onur Demirci, D. John Doyle, Thomas Edrich, Louise Ellard, Matthew R. Eng, Nicole M. Fowler, Ursula Galway, John George, Carin A. Hagberg, David W. Healy, Marshal B. Kaplan, Paul Kempen, Ashish Khanna, Alan Kominsky, Tatyana Kopyeva, Biao Lei, Emad B. Mossad, Vladimir Nekhendzy, Edward Noguera, Megan Nolan, Mauricio Perilla, Marc Popovich, Gazanfar Rahmathulla, Gail I. Randel, William H. Rosenblatt, Twain Russell, Mona Sarkiss, Joseph Scharpf, Tracey Straker, David E. Traul, Robert Weil, Sivan Wexler, David T. Wong, Benjamin Wood, Jie Zhou
- Edited by Basem Abdelmalak, John Doyle
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- Book:
- Anesthesia for Otolaryngologic Surgery
- Published online:
- 05 November 2012
- Print publication:
- 18 October 2012, pp xi-xiv
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- By Nicholas B. Allen, Stephanie Assuras, Robert M. Bilder, Joan C. Borod, John L. Bradshaw, Warrick J. Brewer, Ariel Brown, Nik Brown, Tyrone Cannon, Audrey Carstensen, Cameron S. Carter, Luke Clark, Phyllis Chua, Thilo Deckersbach, Richard A. Depue, Tali Ditman, Aleksey Dumer, David E. Fleck, Lara Foland-Ross, Judith M. Ford, Nelson Freimer, Paolo Fusar-Poli, Nathan A. Gates, Terry E. Goldberg, George Graham, Igor Grant, Melissa J. Green, Michelle M. Halfacre, Wendy Heller, John D. Herrington, Garry D. Honey, Jennifer E. Iudicello, Henry J. Jackson, J. David Jentsch, Donald Kalar, Paul Keedwell, Ester Klimkeit, Nancy S. Koven, Donna A. Kreher, Gina R. Kuperberg, Edythe London, Dan I. Lubman, Daniel H. Mathalon, Patrick D. McGorry, Philip McGuire, George R. Mangun, Gregory A. Miller, Albert Newen, Jack B. Nitschke, Jaak Panksepp, Christos Pantelis, Mary Philips, Russell A. Poldrack, Scott L. Rauch, Susan M. Ravizza, Steven Paul Reise, Nicole Rinehart, Angela Rizk-Jackson, Trevor W. Robbins, Tamara A. Russell, Fred W. Sabb, Cary R. Savage, Kimberley R. Savage, J. Cobb Scott, Marc L. Seal, Larry J. Seidman, Paula K. Shear, Marisa M. Silveri, Nadia Solowij, Laura Southgate, G. Lynn Stephens, D. Stott Parker, Stephen M. Strakowski, Simon A. Surguladze, Kate Tchanturia, René Testa, Janet Treasure, Eve M. Valera, Kai Vogeley, Anthony P. Weiss, Sarah Whittle, Stephen J. Wood, Steven Paul Woods, Murat Yücel, Deborah A. Yurgelun-Todd
- Edited by Stephen J. Wood, University of Melbourne, Nicholas B. Allen, University of Melbourne, Christos Pantelis, University of Melbourne
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- Book:
- The Neuropsychology of Mental Illness
- Published online:
- 10 May 2010
- Print publication:
- 01 October 2009, pp xv-xx
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Transport Properties of Thermoelectric Nanocomposites
- Lilia M Woods, Adian Popescu, Joshua Martin, George S. Nolas
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1166 / 2009
- Published online by Cambridge University Press:
- 31 January 2011, 1166-N05-08
- Print publication:
- 2009
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We present a theoretical model for carrier conductivity and Seebeck coefficient of thermoelectric materials composed of nanogranular regions. The model is used to successfully describe experimental data for chalcogenide PbTe nanocomposites. We also present similar calculations for skutterudite CoSb3 nanocomposites. The carrier scattering mechanism is considered explicitly and it is determined that it is a key factor in the thermoelectric transport process. The grain interfaces are described as potential barriers. We investigate theoretically the role of the barrier heights, widths, and distances between the barriers to obtain an optimum regime for the composites thermoelectric characetristics.
Contributors
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- By Isabella Aboderin, W. Andrew Achenbaum, Katherine R. Allen, Toni C. Antonucci, Sara Arber, Claudine Attias‐Donfut, Paul B. Baltes, Sandhi Maria Barreto, Vern L. Bengtson, Simon Biggs, Joanna Bornat, Julie B. Boron, Mike Boulton, Clive E. Bowman, Marjolein Broese van Groenou, Edna Brown, Robert N. Butler, Bill Bytheway, Neena L. Chappell, Neil Charness, Kaare Christensen, Peter G. Coleman, Ingrid Arnet Connidis, Neal E. Cutler, Sara J. Czaja, Svein Olav Daatland, Lia Susana Daichman, Adam Davey, Bleddyn Davies, Freya Dittmann‐Kohli, Glen H. Elder, Carroll L. Estes, Mike Featherstone, Amy Fiske, Alexandra Freund, Daphna Gans, Linda K. George, Roseann Giarrusso, Chris Gilleard, Jay Ginn, Edlira Gjonça, Elena L. Grigorenko, Jaber F. Gubrium, Sarah Harper, Jutta Heckhausen, Akiko Hashimoto, Jon Hendricks, Mike Hepworth, Charlotte Ikels, James S. Jackson, Yuri Jang, Bernard Jeune, Malcolm L. Johnson, Randi S. Jones, Alexandre Kalache, Robert L. Kane, Rosalie A. Kane, Ingrid Keller, Rose Anne Kenny, Thomas B. L. Kirkwood, Kees Knipscheer, Martin Kohli, Gisela Labouvie‐Vief, Kristina Larsson, Shu‐Chen Li, Charles F. Longino, Ariela Lowenstein, Erick McCarthy, Gerald E. McClearn, Brendan McCormack, Elizabeth MacKinlay, Alfons Marcoen, Michael Marmot, Tom Margrain, Victor W. Marshall, Elizabeth A. Maylor, Ruud ter Meulen, Harry R. Moody, Robert A. Neimeyer, Demi Patsios, Margaret J. Penning, Stephen A. Petrill, Chris Phillipson, Leonard W. Poon, Norella M. Putney, Jill Quadagno, Pat Rabbitt, Jennifer Reid Keene, Sandra G. Reynolds, Steven R. Sabat, Clive Seale, Merril Silverstein, Hannes B. Staehelin, Ursula M. Staudinger, Robert J. Sternberg, Debra Street, Philip Taylor, Fleur Thomése, Mats Thorslund, Jinzhou Tian, Theo van Tilburg, Fernando M. Torres‐Gil, Josy Ubachs‐Moust, Christina Victor, K. Warner Shaie, Anthony M. Warnes, James L. Werth, Sherry L. Willis, François‐Charles Wolff, Bob Woods
- Edited by Malcolm L. Johnson, University of Bristol
- Edited in association with Vern L. Bengtson, University of Southern California, Peter G. Coleman, University of Southampton, Thomas B. L. Kirkwood, University of Newcastle upon Tyne
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- Book:
- The Cambridge Handbook of Age and Ageing
- Published online:
- 05 June 2016
- Print publication:
- 01 December 2005, pp xii-xvi
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Investigation of the Causes and Variation of Leakage Currents in Amorphous Silicon P-I-N Diodes
- Todd R. Johnson, Gautam Ganguly, George S. Wood, David E. Carlson
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- Journal:
- MRS Online Proceedings Library Archive / Volume 762 / 2003
- Published online by Cambridge University Press:
- 01 February 2011, A7.7
- Print publication:
- 2003
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Excess leakage currents under reverse bias (known as shunting) and spontaneous reductions of this excess leakage under increased reverse bias (known as curing) were investigated in hydrogenated amorphous silicon (a-Si:H) based single junction p-i-n type diodes. An increase in the frequency of shunting was observed when the front contacts were switched from tin oxide to zinc oxide, most likely due to defects in the previously deposited zinc oxide coated glass was observed. Storage in the dark and light soaking up to 100 hours were both observed to independently increase the leakage current in previously leaking diodes. Models for the distribution of shunt-causing defects within a given cell area were considered. Comparing the measured frequency of shunting using cells of varying area (1 to 16 mm2) to the models' predictions indicate a distribution of point defects separated by relatively large average distances that are slightly larger for tin oxide (5-6 mm) than for zinc oxide (4 mm).