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Neurobiological correlates of antisociality across adolescence and young adulthood: a multi-sample, multi-method study
- Neeltje E. Blankenstein, Mark de Rooij, Joost van Ginkel, Tom F. Wilderjans, Esther L. de Ruigh, Helena C. Oldenhof, Josjan Zijlmans, Tijs Jambroes, Evelien Platje, Marjan de Vries-Bouw, Susan Branje, Wim H. J. Meeus, Robert R. J. M. Vermeiren, Arne Popma, Lucres M. C. Jansen
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- Journal:
- Psychological Medicine / Volume 53 / Issue 5 / April 2023
- Published online by Cambridge University Press:
- 27 August 2021, pp. 1834-1849
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Background
Antisociality across adolescence and young adulthood puts individuals at high risk of developing a variety of problems. Prior research has linked antisociality to autonomic nervous system and endocrinological functioning. However, there is large heterogeneity in antisocial behaviors, and these neurobiological measures are rarely studied conjointly, limited to small specific studies with narrow age ranges, and yield mixed findings due to the type of behavior examined.
MethodsWe harmonized data from 1489 participants (9–27 years, 67% male), from six heterogeneous samples. In the resulting dataset, we tested relations between distinct dimensions of antisociality and heart rate, pre-ejection period (PEP), respiratory sinus arrhythmia, respiration rate, skin conductance levels, testosterone, basal cortisol, and the cortisol awakening response (CAR), and test the role of age throughout adolescence and young adulthood.
ResultsThree dimensions of antisociality were uncovered: ‘callous-unemotional (CU)/manipulative traits’, ‘intentional aggression/conduct’, and ‘reactivity/impulsivity/irritability’. Shorter PEPs and higher testosterone were related to CU/manipulative traits, and a higher CAR is related to both CU/manipulative traits and intentional aggression/conduct. These effects were stable across age.
ConclusionsAcross a heterogeneous sample and consistent across development, the CAR may be a valuable measure to link to CU/manipulative traits and intentional aggression, while sympathetic arousal and testosterone are additionally valuable to understand CU/manipulative traits. Together, these findings deepen our understanding of the fundamental mechanisms underlying different components of antisociality. Finally, we illustrate the potential of using current statistical techniques for combining multiple datasets to draw robust conclusions about biobehavioral associations.
Meanings of ‘lifecycle robust neighbourhoods’: constructing versus attaching to places
- SUSAN VAN HEES, KLASIEN HORSTMAN, MARIA JANSEN, DIRK RUWAARD
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- Journal:
- Ageing & Society / Volume 38 / Issue 6 / June 2018
- Published online by Cambridge University Press:
- 23 January 2017, pp. 1148-1173
- Print publication:
- June 2018
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In Western welfare states, notions of age-friendly communities and ageing-in-place are increasingly important in new health policies. In the Netherlands, care reforms are modifying the former welfare state to be more participatory; local governments are seeking collaborative solutions. Municipalities and housing, care and welfare organisations in the southern part of the country developed the concept of ‘lifecycle robust neighbourhoods’, envisioned as places where older people can age-in-place. Although many scholars have used the concept ageing-in-place in their studies of neighbourhoods, we aim to unravel this concept further by exploring how this particular ageing policy plays out in practice. This paper explores what the development of ‘lifecycle robust neighbourhoods’ means in relation to notions of ageing-in-place and age-friendly communities. We used ethnography (interviews, observations and focus groups) to reveal how, on the one hand, the policy makers, housing, care and welfare directors and representatives of older people, as developers of ‘lifecycle robust neighbourhoods’ and, on the other hand, older people, give meaning to places to age-in-place. It becomes clear that ageing-in-place has a different meaning in policy discourses than in practice. While developers mainly considered place as something construable, older people emotionally attached to place through lived experiences.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. Nicholson, George W. E. Nickelsburg, Tatyana Nikolskaya, Damayanthi M. A. Niles, Bertil Nilsson, Nyambura Njoroge, Fidelis Nkomazana, Mary Beth Norton, Christian Nottmeier, Sonene Nyawo, Anthère Nzabatsinda, Edward T. Oakes, Gerald O'Collins, Daniel O'Connell, David W. Odell-Scott, Mercy Amba Oduyoye, Kathleen O'Grady, Oyeronke Olajubu, Thomas O'Loughlin, Dennis T. Olson, J. Steven O'Malley, Cephas N. Omenyo, Muriel Orevillo-Montenegro, César Augusto Ornellas Ramos, Agbonkhianmeghe E. Orobator, Kenan B. Osborne, Carolyn Osiek, Javier Otaola Montagne, Douglas F. Ottati, Anna May Say Pa, Irina Paert, Jerry G. Pankhurst, Aristotle Papanikolaou, Samuele F. Pardini, Stefano Parenti, Peter Paris, Sung Bae Park, Cristián G. Parker, Raquel Pastor, Joseph Pathrapankal, Daniel Patte, W. Brown Patterson, Clive Pearson, Keith F. Pecklers, Nancy Cardoso Pereira, David Horace Perkins, Pheme Perkins, Edward N. Peters, Rebecca Todd Peters, Bishop Yeznik Petrossian, Raymond Pfister, Peter C. Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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How does the Support Influence the Catalytic Activity of the Keggin Ion?
- Zakiyyah Smith, Michael Palmieri, Nancy Buecheler, Susan A. Jansen
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- MRS Online Proceedings Library Archive / Volume 454 / 1996
- Published online by Cambridge University Press:
- 10 February 2011, 103
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- 1996
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Heteropoly acids, HPA are well known solid acid and oxidation catalysts that find application in hetergeneous and homogeneous reactions. In the former, surface area and stability problems are diminshed by supporting the HPA. Typical supports include oxide substrates and porous carbon materials. The HPA's show some instability on these supports however. In this work, we demonstrate that HPA encapsulated in sol-gel silica matrices show enhanced catalytic performance without compromising the catalytic activity of the HPA. In addition, the specific role of the support in the catalytic process is described as well.
Activation of Oxidation Catalysts by Solvation
- Annette D. Eddowes, Dana Stallings, Caprice L. Hightower, Susan A. Jansen
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- MRS Online Proceedings Library Archive / Volume 454 / 1996
- Published online by Cambridge University Press:
- 10 February 2011, 253
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- 1996
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The versatility of heteropolyanions implies many different uses for Keggin type catalysts. However, new roles for these catalysts must first be preceeded by further understanding of the mechanisms by which they operate. It has been observed that the solvation and/or complexation of heteropolyanions promotes or limits activity in homogeneous chemistry. For this reason the solution state and the solvation characteristics of the catalyst were studied in oxidation and photochemical reactions. Simple oxidation reactions provide a system by which the solution state of the catalyst can be studied. The catalyst used for these mechanistic studies is the Keggin ion (PMo10V2O40)−5.
Assessment of Polyanilines as Alternative Anti-Corrosion Materials: A Theoretical Analysis of Metal-Polymer Adhesion.
- Robert Vallerio, Roy Keyer, Steve Grabania, Mary Landis, Susan Jansen, Yen Wei
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- MRS Online Proceedings Library Archive / Volume 413 / 1995
- Published online by Cambridge University Press:
- 10 February 2011, 523
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- 1995
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Current corrosion control methods use coatings which are toxic and environmentally hazardous materials, such as, chromium. More work needs to be done to find a substitute that is competitive with current industrial technologies. Many polymeric materials have been tested as possible alternatives to the present systems. These include polysiloxanes, polymer blends based on polymethylmethacrylate/polysiloxanes and co-polymers of these materials. [1] Oxidized and carbided metal surfaces have been analyzed as chromium substitutes as well. [2] So far the technology has not advanced to a industrially competitive level. Polyaniline is on of the most promising materials for environmentally safe corrosion control.
Catalytic Implications for Keggin and Dawson Ions: A Theoretical Study of Stability Factors of Heteropolyoxoanions
- Shu-Hsien Wang, Susan A. Jansen
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- MRS Online Proceedings Library Archive / Volume 368 / 1994
- Published online by Cambridge University Press:
- 15 February 2011, 229
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- 1994
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Hetreropolyoxoanions(HPAs) have received wide spread attention due to their unique oxidation-reduction properties in catalysis. Two main structural motifs groups of HPAs have been described by Keggin and Dawson. The first is composed of twelve distorted, octahedrallycoordinated metal atoms forming trimeric and tetrameric subunits connected such that a closed shell results. The second is formed by fusing two Keggin units. The most common Keggin ions(XM12O40n−,) with Td symmetry and the Dawson ions(X2M18O62n−) with D3h symmetry are the α-isomers; while the β-isomers are generated by rotating one trimer 60° along its C3 axis, thus producing the Cs, symmetry for β-Keggin ions and D34 symmetry for β-Dawson ions. Here, M is the framework metal atom, usually Mo, W, and X is the central heteroatom which can be the metal or nonmetal. From our previous studies, the instability of β-isomers caused by the “rotated” trimer can not be compensated by other coordination effects within the cluster and therefore defect states are retained between the HOMO-LUMO gap relative to the α-isomer. This enhances catalytic properties and causes thermal/photo lability. The catalytic function of a-Keggin ions are well studied; however, related research reports about Dawson ions are rare. The α-Dawson ion possesses stronger oxidizing ability and higher activities in oxidative dehydrogenation and oxygen addition reactions than the α-Keggin ions; the β-isomers have a greater tendency to be reduced than the α-isomers. Most of the characterization methods applied have not yielded the electronic or the structural requisites for the catalytic properties of the HPAs. In this work, the theoretical analysis is done through the application of crystal/tight binding theory coupled with the extended HMckel methodology. The stability trends and the redox behaviors provided by this work reliably trace the experimental data. In addition, the intrinsic instability and the redox effects in the β-isomers with respect to the α-isomers is assessed and a rationale for the observed catalytic and electronic develpoment of structrual function is also offered.
An Assessment of Electronic Exchange in Phosphomolybdates
- David J. Singh, Susan A. Jansen, Harry Mazurek, Guy Crocco
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- MRS Online Proceedings Library Archive / Volume 206 / 1990
- Published online by Cambridge University Press:
- 28 February 2011, 309
- Print publication:
- 1990
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In the synthesis of polyacrylates, a necessary step involves the conversion of acroleins to acrylic acids- a process catalysed by Mo oxides. We have directed our work towards the elucidation of the electronic structure of the most stable structure of 12-heteromolybdate, ie. the α-keggin unit, using EPR spectroscopy, Cyclic Voltammetry, and molecular orbital calculations based on the extended Huckel theory. Metal ion substitution has been shown to have negligible effect on the electronic structure of the keggin unit thus rationalising previous arguments of structural rigidity. Electronic exchange has been shown to be facilitated through metal-metal interaction.
Crystallization and Matrix Effects on the Electronic Properties of Polymers Doped with CT Salts of TCNQ
- Yang-Cheng Fann, Susan A. Jansen, Marygail Hutchins
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- Journal:
- MRS Online Proceedings Library Archive / Volume 214 / 1990
- Published online by Cambridge University Press:
- 22 February 2011, 107
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- 1990
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Molecularly doped polymer films have shown potential for applications in electrophotography and molecular electronics. The electrooptical and magnetic properties as well as conductivities are enhanced significantly by doping chargetransfer(CT) complexes or dye into a polymeric matrix, by comparison with nondoped polymer films.
Polycarbonate films doped with CT complexes based on 7,7′,8,8′- tetracyanoquinodimethane( TCNQ) were studied from 100K to 450K. Crystallization and formation of ‘nearly’ spaced aggregates within the polymer matrix were observed. These phenomena were affected by several factors such as the film thickness, evaporation process, temperature and concentration within the polymer matrix. Discontinuities in magnetic properties at 200K, possibly due to solvent encapsulation in the matrix, and at about 385K due to glass transition of the polymer were observed.
Characterization, conductivity measurements in comparison with pristine complexes, and photoirradiation studies on these doped films are presented.
Electron Paramagnetic Resonance Studies of Donor-Acceptor Salts in Polymer Media
- Yang-Cheng Fann, Susan Ann Jansen
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- Journal:
- MRS Online Proceedings Library Archive / Volume 173 / 1989
- Published online by Cambridge University Press:
- 25 February 2011, 161
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- 1989
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Charge transfer complexes, their inherent electrical conductivity, magnetic properties and donor-acceptor redox relationships have been a focus of much research in the last several years. One direction has been in the design of memory devices and applications in molecular electronics.1,2 Our work has focused on analysis of such processes in a polymeric medium. Polycarbonate films of 7,7’,8,8’-Tetracyanoquinodimethane (TCNQ) and o-tolidine (o-T) complexes were studied by EPR spectroscopy from 100-300K. EPR spectra and magnetic susceptibility of the dispersed charge-transfer complexes are presented and compared with the pristine materials. These studies were carried out as a function of donor/acceptor stoichiometry and concentration within the polymer matrix. Saturation studies show significant differences as the composition varies. In addition the g-tensor and linewidth are strongly dependent on temperature and composition.