13 results
Simulations of radiatively cooled magnetic reconnection driven by pulsed power
- Rishabh Datta, Aidan Crilly, Jeremy P. Chittenden, Simran Chowdhry, Katherine Chandler, Nikita Chaturvedi, Clayton E. Myers, William R. Fox, Stephanie B. Hansen, Chris A. Jennings, Hantao Ji, Carolyn C. Kuranz, Sergey V. Lebedev, Dmitri A. Uzdensky, Jack D. Hare
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- Journal:
- Journal of Plasma Physics / Volume 90 / Issue 2 / April 2024
- Published online by Cambridge University Press:
- 19 April 2024, 905900215
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Magnetic reconnection is an important process in astrophysical environments, as it reconfigures magnetic field topology and converts magnetic energy into thermal and kinetic energy. In extreme astrophysical systems, such as black hole coronae and pulsar magnetospheres, radiative cooling modifies the energy partition by radiating away internal energy, which can lead to the radiative collapse of the reconnection layer. In this paper, we perform two- and three-dimensional simulations to model the MARZ (Magnetic Reconnection on Z) experiments, which are designed to access cooling rates in the laboratory necessary to investigate reconnection in a previously unexplored radiatively cooled regime. These simulations are performed in GORGON, an Eulerian two-temperature resistive magnetohydrodynamic code, which models the experimental geometry comprising two exploding wire arrays driven by 20 MA of current on the Z machine (Sandia National Laboratories). Radiative losses are implemented using non-local thermodynamic equilibrium tables computed using the atomic code Spk, and we probe the effects of radiation transport by implementing both a local radiation loss model and $P_{1/3}$ multi-group radiation transport. The load produces highly collisional, super-Alfvénic (Alfvén Mach number $M_A \approx 1.5$), supersonic (Sonic Mach number $M_S \approx 4-5$) strongly driven plasma flows which generate an elongated reconnection layer (Aspect Ratio $L/\delta \approx 100$, Lundquist number $S_L \approx 400$). The reconnection layer undergoes radiative collapse when the radiative losses exceed the rates of ohmic and compressional heating (cooling rate/hydrodynamic transit rate = $\tau _{\text {cool}}^{-1}/\tau _{H}^{-1}\approx 100$); this generates a cold strongly compressed current sheet, leading to an accelerated reconnection rate, consistent with theoretical predictions. Finally, the current sheet is also unstable to the plasmoid instability, but the magnetic islands are extinguished by strong radiative cooling before ejection from the layer.
Identifying significant correlates of purpose in life in older US military veterans: results from the national health and resilience in veterans study
- Ian C. Fischer, David B. Feldman, Jack Tsai, Ilan Harpaz-Rotem, Katherine A. Lucas, Stefan E. Schulenberg, Robert H. Pietrzak
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- Journal:
- International Psychogeriatrics / Volume 35 / Issue 10 / October 2023
- Published online by Cambridge University Press:
- 30 January 2023, pp. 560-565
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Objective:
Perceived purpose in life (PIL) has been linked to a broad range of adverse physical, mental, and cognitive outcomes. However, limited research has examined factors associated with PIL that can be targeted in prevention and treatment efforts in aging populations at heightened risk of adverse outcomes. Using data from predominantly older US veterans, we sought to identify important correlates of PIL.
Methods:Cross-sectional data were analyzed from the 2019–2020 National Health and Resilience in Veterans Study, which surveyed a nationally representative sample of 4069 US military veterans (Mage = 62.2). Elastic net and relative importance analyses were conducted to evaluate sociodemographic, military, health, and psychosocial variables that were strongly associated with PIL.
Results:Of the 39 variables entered into an elastic net analysis, 10 were identified as significant correlates of PIL. In order of magnitude, these were resilience (18.7% relative variance explained [RVE]), optimism (12.1%), depressive symptoms (11.3%), community integration (10.7%), gratitude (10.2%), loneliness (9.8%), received social support (8.6%), conscientiousness (8.5%), openness to experience (5.4%), and intrinsic religiosity (4.7%).
Conclusions:Several modifiable psychosocial factors emerged as significant correlates of PIL in US military veterans. Interventions designed to target these factors may help increase PIL and mitigate risk for adverse health outcomes in this population.
Facilitating Real-Time, Multidirectional Learning for Clinicians in a Low-Evidence Pandemic Response
- Richard C Hunt, Sofia P Braunstein, Lauren Cuddy Egbert, Katherine A Gorbach, Monisha Rao, Jonathan D Pearson, Amy J Armistad, Sanjeev Arora, Celine A Bennett, Amanda M Dezan, Jack Herrmann, John T Redd, B. Tilman Jolly, Jon R Krohmer, Bruce B Struminger
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- Journal:
- Disaster Medicine and Public Health Preparedness / Volume 17 / 2023
- Published online by Cambridge University Press:
- 21 September 2022, e246
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As COVID-19 was declared a health emergency in March 2020, there was immense demand for information about the novel pathogen. This paper examines the clinician-reported impact of Project ECHO COVID-19 Clinical Rounds on clinician learning. Primary sources of study data were Continuing Medical Education (CME) Surveys for each session from the dates of March 24, 2020 to July 30, 2020 and impact surveys conducted in November 2020, which sought to understand participants’ overall assessment of sessions. Quantitative analyses included descriptive statistics and Mann-Whitney testing. Qualitative data were analyzed through inductive thematic analysis. Clinicians rated their knowledge after each session as significantly higher than before that session. 75.8% of clinicians reported they would ‘definitely’ or ‘probably’ use content gleaned from each attended session and clinicians reported specific clinical and operational changes made as a direct result of sessions. 94.6% of respondents reported that COVID-19 Clinical Rounds helped them provide better care to patients. 89% of respondents indicated they ‘strongly agree’ that they would join ECHO calls again.COVID-19 Clinical Rounds offers a promising model for the establishment of dynamic peer-to-peer tele-mentoring communities for low or no-notice response where scientifically tested or clinically verified practice evidence is limited.
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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- Book:
- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
- Print publication:
- 27 April 2015, pp ix-xxx
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Panic-Agoraphobic Spectrum and Cardiovascular Disease
- Mario Miniati, Mauro Mauri, Liliana Dell'Osso, Stefano Pini, Francesco Mengali, Katherine Shear, Jack D. Maser, Victoria Grochocinski, Ellen Frank, Giovanni B. Cassano
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- Journal:
- CNS Spectrums / Volume 3 / Issue 4 / April 1998
- Published online by Cambridge University Press:
- 07 November 2014, pp. 58-62
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Panic disorder occurs frequently with different forms of cardiovascular disease and hypertension. The 13 panic symptoms described in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) often overlap with manifestations of cardiovascular disorders, raising problems in the differential diagnosis. In order to explore in greater detail the phenomenology of panic symptoms in cardiovascular patients, the Structured Clinical Interview for Panic-Agoraphobic Spectrum (SCI-PAS) was administered to 111 patients with hypertension and 29 patients with a recent myocardial infarction.
With regard to the frequency of endorsement of many of the symptoms assessed on the SCI-PAS, more than 40% of the cardiovascular patients who failed to meet the DSM-IV criteria for panic disorder did not significantly differ from the 10% of cardiovascular patients who did fulfill the criteria for panic disorder. A third distinct subgroup comprising 48.6% of the cardiovascular patients reported a significantly smaller number of SCI-PAS symptoms than the other two groups.
These preliminary findings suggest the existence of a relatively large proportion of cardiovascular patients who present with physical and psychological symptoms that are potentially related to panic disorder and that may provoke considerable subjective distress. Further studies are needed to clarify the nature of these symptoms and their potential interference with treatment and symptomatology of cardiovascular disease.
The Panic-Agoraphobic Spectrum: Rationale, Assessment, and Clinical Usefulness
- Giovanni B. Cassano, Alessandro Rotondo, Jack D. Maser, M. Katherine Shear, Ellen Frank, Mauro Mauri, Liliana Dell'Osso
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- CNS Spectrums / Volume 3 / Issue 4 / April 1998
- Published online by Cambridge University Press:
- 07 November 2014, pp. 35-48
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This paper describes a model of psychopathology termed the panic-agoraphobic spectrum. The model has been constructed by identifying different psychopathologic and clinical domains that incorporate and extend the diagnosis of panic disorder as described in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV).
Categorical classifications do not take into account the subthreshold, atypical, and often enduring symptoms that accompany the core manifestations of full-blown mental disorders. These often-neglected spectrums of symptoms, however, may be as distressing and debilitating as the full-blown disorders and can have unrecognized importance in selection of and response to treatment. At the Department of Psychiatry, Neurobiology, Pharmacology, and Biotechnology, Institute of Psychiatry of the University of Pisa, Italy, a spectrum approach to mental disorders (eg, bipolar, obsessive-compulsive, eating, and panic disorders) has been used extensively and has proven effective in clinical practice.
The need for systematic identification and assessment of a broad array of symptoms and behavioral features has led, as a first step, to the conceptualization of the panic-agoraphobic spectrum model. In collaboration with researchers from the University of Pittsburgh, PA, and elsewhere, the University of Pisa scientists have further refined the panic-agoraphobic spectrum model and have developed a structured interview for this spectrum called the Structured Clinical Interview for Panic-Agoraphobic Spectrum. The rationale, clinical usefulness, and heuristic significance of the panic-agoraphobic spectrum model are discussed below.
The Spectrum Model: A More Coherent Approach to the Complexity of Psychiatric Symptomatology
- Ellen Frank, Giovanni B. Cassano, M. Katherine Shear, Alessandro Rotondo, Liliana Dell'Osso, Mauro Mauri, Jack Maser, Victoria Grochocinski
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- Journal:
- CNS Spectrums / Volume 3 / Issue 4 / April 1998
- Published online by Cambridge University Press:
- 07 November 2014, pp. 23-34
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The current tools used to define and diagnose mental disorders, including the Diagnostic and Statistical Manual of Mental Disorders and the International Classification of Diseases, have added specificity to the psychiatric nomenclature. However, their stereotypic rigidity in classification has resulted in the failure to identify the full range of potentially debilitating psychiatric symptoms with which patients may present. A spectrum model of psychopathology is more adept at recognizing the subclinical or threshold symptomatology that may occur concomitantly with core psychiatric disorders. The authors discuss the development of a spectrum approach to the diagnosis of mental disorders, which offers the potential to improve treatment selection and therapeutic outcomes.
Note on contributors
- Edited by Mark Bradley, University of Nottingham
- With Kenneth Stow, University of Haifa, Israel
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- Book:
- Rome, Pollution and Propriety
- Published online:
- 05 August 2012
- Print publication:
- 26 July 2012, pp xii-xvi
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Metal-catalyzed graphitization in Ni-C alloys and amorphous-C/Ni bilayers
- Katherine L. Saenger, Christian Lavoie, Roy Carruthers, Ageeth A. Bol, Timothy J. Mcardle, Jack O. Chu, James C. Tsang, Alfred Grill
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1284 / 2011
- Published online by Cambridge University Press:
- 01 March 2011, mrsf10-1284-c03-01
- Print publication:
- 2011
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Metal-catalyzed graphitization from vapor phase sources of carbon is now an established technique for producing few-layer graphene, a candidate material of interest for post-silicon electronics. Here we describe two alternative metal-catalyzed graphene formation processes utilizing solid phase sources of carbon. In the first, carbon is introduced as part of a cosputtered Ni-C alloy; in the second, carbon is introduced as one of the layers in an amorphous carbon (a-C)/Ni bilayer stack. We examine the quality and characteristics of the resulting graphene as a function of starting film thicknesses, Ni-C alloy composition or a-C deposition method (physical or chemical vapor deposition), and annealing conditions. We then discuss some of the competing processes playing a role in graphitic carbon formation and review recent evidence showing that the graphitic carbon in the a-C/Ni system initially forms by a metal-induced crystallization mechanism (analogous to what is seen with Al-induced crystallization of amorphous Si) rather than by the dissolution-upon-heating/precipitation-upon-cooling mechanism seen when graphene is grown by metal-catalyzed chemical vapor deposition methods.
Multivariate techniques and their application in nutrition: a metabolomics case study
- E. Katherine Kemsley, Gwénaëlle Le Gall, Jack R. Dainty, Andrew D. Watson, Linda J. Harvey, Henri S. Tapp, Ian J. Colquhoun
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- Journal:
- British Journal of Nutrition / Volume 98 / Issue 1 / July 2007
- Published online by Cambridge University Press:
- 01 July 2007, pp. 1-14
- Print publication:
- July 2007
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The post-genomic technologies are generating vast quantities of data but many nutritional scientists are not trained or equipped to analyse it. In high-resolution NMR spectra of urine, for example, the number and complexity of spectral features mean that computational techniques are required to interrogate and display the data in a manner intelligible to the researcher. In addition, there are often multiple underlying biological factors influencing the data and it is difficult to pinpoint which are having the most significant effect. This is especially true in nutritional studies, where small variations in diet can trigger multiple changes in gene expression and metabolite concentration. One class of computational tools that are useful for analysing this highly multivariate data include the well-known ‘whole spectrum’ methods of principal component analysis and partial least squares. In this work, we present a nutritional case study in which NMR data generated from a human dietary Cu intervention study is analysed using multivariate methods and the advantages and disadvantages of each technique are discussed. It is concluded that an alternative approach, called feature subset selection, will be important in this type of work; here we have used a genetic algorithm to identify the small peaks (arising from metabolites of low concentration) that have been altered significantly following a dietary intervention.
Attention function after childhood stroke
- JEFFREY E. MAX, DONALD A. ROBIN, H. GERRY TAYLOR, KEITH O. YEATES, PETER T. FOX, JACK L. LANCASTER, FACUNDO F. MANES, KATHERINE MATHEWS, SHANNON AUSTERMANN
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- Journal:
- Journal of the International Neuropsychological Society / Volume 10 / Issue 7 / November 2004
- Published online by Cambridge University Press:
- 01 November 2004, pp. 976-986
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We investigated attentional outcome after childhood stroke and orthopedic diagnosis in medical controls. Twenty-nine children with focal stroke lesions and individually matched children with clubfoot or scoliosis were studied with standardized attention and neuroimaging assessments. Stroke lesions were quite varied in location and commonly involved regions implicated in Posner's model of attention networks. Children with stroke lesions performed significantly more poorly regarding attention function compared with controls. Performance on the Starry Night, a test demanding alerting and sensory-orienting but not executive attention function, was significantly associated with lesion size in the alerting and sensory-orienting networks but not the executive attention network. Furthermore, earlier age at lesion acquisition was significantly associated with poorer attention function even when lesion size was controlled. These findings support the theory of dissociable networks of attention and add to evidence from studies of children with diffuse and focal brain damage that early insults are associated with worse long-term outcomes in many domains of neuropsychological function. In addition, these results may provide clues towards the understanding of mechanisms underlying attention in children. (JINS, 2004, 10, 976–986.)
Attention deficit hyperactivity disorder and neurocognitive correlates after childhood stroke
- Jeffrey E. Max, Katherine Mathews, Facundo F. Manes, Brigitte A.M. Robertson, Peter T. Fox, Jack L. Lancaster, Amy E. Lansing, Amy Schatz, Nicole Collings
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- Journal:
- Journal of the International Neuropsychological Society / Volume 9 / Issue 6 / September 2003
- Published online by Cambridge University Press:
- 27 August 2003, pp. 815-829
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We investigated the frequency and neurocognitive correlates of attention deficit hyperactivity disorder and traits of this disorder (ADHD/Traits) after childhood stroke and orthopedic diagnosis in medical controls. Twenty-nine children with focal stroke lesions and individually matched children with clubfoot or scoliosis were studied with standardized psychiatric, intellectual, academic, adaptive, executive, and motivation function assessments. Lifetime ADHD/Traits were significantly more common in stroke participants with no prestroke ADHD than in orthopedic controls (16/28 vs. 7/29; Fisher's Exact p < .02). Lifetime ADHD/Traits in the orthopedic controls occurred exclusively in males with clubfoot (7/13; 54%). Participants with current ADHD/Traits functioned significantly worse (p < .005) than participants without current ADHD/Traits on all outcome measures. Within the stroke group, current ADHD/Traits was associated with significantly lower verbal IQ and arithmetic achievement (p < .04), more nonperseverative errors (p < .005), and lower motivation (p < .004). A principal components analysis of selected outcome variables significantly associated with current ADHD/Traits revealed “impaired neurocognition” and “inattention-apathy” factors. The latter factor was a more consistent predictor of current ADHD/Traits in regression analyses. These findings suggest that inattention and apathy are core features of ADHD/Traits after childhood stroke. This association may provide clues towards the understanding of mechanisms underlying the syndrome. (JINS, 2003, 9, 815–829.)
14 - Traditions in wild white-faced capuchin monkeys
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- By Susan Perry, Assistant Professor in the Department of Anthropology, University of California, Los Angeles, Melissa Panger, Department of Anthropology, George Washington University, 2110 G St. NW, Washington, DC 20052, USA, Lisa M. Rose, Department of Anthropology and Sociology, University of British Columbia. 6303 NW Marine Drive, Vancouver, British Columbia, V6T, Mary Baker, Department of Anthropology, Whittier College, 13406 Philadelphia St., Whittier, CA 90608, USA, Julie Gros-Louis, Department of Psychology, University of Indiana, 1101 E. 10th St., Bloomington, IN 47405, USA, Katherine Jack, Department of Anthropology, Appalachian State University, Boone, NC 28608, USA, Katherine C. Mackinnon, Department of Sociology and Criminal Justice, Saint Louis University, 3500 Lindell Boulevard, St. Louis, MO 63103, USA, Joseph Manson, Max-Planck-Institut für evolutionäre Anthropologie, Inselstraße 22, 04103 Leipzig, Germany, Linda Fedigan, Department of Anthropology, University of Calgary, Calgary, Alberta T2N 1N4, Canada, Kendra Pyle, Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Edited by Dorothy M. Fragaszy, University of Georgia, Susan Perry, University of California, Los Angeles
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- Book:
- The Biology of Traditions
- Published online:
- 27 October 2009
- Print publication:
- 03 July 2003, pp 391-425
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Summary
Introduction
Primatologists have long recognized that social learning could play an important role in food choice and food processing in primates, since the discovery (by Itani in 1958) of innovative food-processing techniques disseminated among Japanese macaques (see Ch. 10 for a review of subsequent findings). It is somewhat surprising that, after the initial discovery of the importance of social learning in Japanese macaques, practically all subsequent research on social learning in wild nonhuman primates has been on apes (e.g. Boesch, 1996a, 1996b; Boesch and Boesch-Achermann, 2000; Boesch and Tomasello, 1998; McGrew, 1992, 1998; van Schaik, Deaner, and Merrill, 1999; Whiten et al., 1999; see Chs. 10 and 11). To remedy the gap in what we know about social learning in natural settings in other primates, and because a truly comparative framework is necessary to understand the biological underpinnings of social learning (see Ch. 1), we began a comprehensive study of social learning in wild capuchin monkeys (Cebus spp.). Our study investigates the probable role of social learning in a number of behavioral domains.
Capuchins seem particularly likely to exhibit extensive reliance on learning, and social learning in particular, for the following reasons (Fragaszy, Visalberghi, and Fedigan, 2003). Several aspects of capuchin ecology promote behavioral flexibility. First, the genus Cebus occupies a wider geographic area than any other New World genus apart from Alouatta (Emmons, 1997), and it uses many different habitat types. Therefore, capuchins face a wide variety of environmental challenges.