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93 Investigating the minimal requirements for startup procurement by healthcare institutions in Ontario, Canada
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- Zoya Aziz Bhatti, Joseph Ferenbok, Derek Choi, Zoya Bhatti, Jospeh Ferenbok, Edyta Marcon, Marissa Bird, Juli Smyth, Bibaswan Ghoshal
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- Journal:
- Journal of Clinical and Translational Science / Volume 8 / Issue s1 / April 2024
- Published online by Cambridge University Press:
- 03 April 2024, p. 25
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OBJECTIVES/GOALS: The primarygoal is to understand the challenges and barriers associated with the procurement of innovative technologies.Specifically, our research will answer the following question: what are the minimal requirements for a startup’s solution to beprocuredby anOntariohealthcare institution? METHODS/STUDY POPULATION: Participants will include procurement professionals at startups, healthcare institutions, and procurement facilitating agencies. Semi-structured interviews will be conducted in order to understand different procurement pathways and the possible procurement related gaps or barriers that startups face. Through qualitative ethnographic methods, participant interviews will characterize existing relationships and examine the rationale behind startup procurement decision-making. Data collection will include recordings, verbatim transcripts, and researcher field notes. Through inductive qualitative analysis, the data will be examined to build an intervention to assist in startup procurement. RESULTS/ANTICIPATED RESULTS: Our investigation will yield insight into expectations between hospital procurement requirements and startup procurement. The qualitative analysis will identify targets for engagement, and appropriate actors that can bridge gaps. Our results will identify pathways for procurement and the minimal procurement requirements to aid startup procurement planning. Our research will support innovators by delivering an intervention that will enable easier implementation of market ready solutions in a Canadian context. In line with principles from the National Center for Advancing Translational Sciences, this research can be used towards enhancing efficiency, speed of translation, and innovation. DISCUSSION/SIGNIFICANCE: We will contextualize the needs of start-ups and empower them to understand their procurement ecosystem. Facilitating better navigation of the procurement space allows for innovators to present solutions that healthcare organizations can adopt, resulting in improved clinical and patient outcomes.
3071 Cell Survival in Corneal Endothelial Dystrophies
- Rajalekshmy Shyam, Diego Ogando, Moonjung Choi, Joseph Bonanno
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- Journal:
- Journal of Clinical and Translational Science / Volume 3 / Issue s1 / March 2019
- Published online by Cambridge University Press:
- 26 March 2019, p. 4
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OBJECTIVES/SPECIFIC AIMS: Purpose - The goal of this study is to understand how loss of the membrane protein SLC4A11 alters endothelial cell metabolism thereby producing Corneal Endothelial Dystrophy. Studies from our lab indicated that glutamine-dependent mitochondrial dysfunction is one of the outcomes of SLC4a11 loss. In the current study, we ask if autophagy and mitophagy pathways and the signaling pathways that regulate these processes are altered in SLC4a11 KO cells. METHODS/STUDY POPULATION: Methods – Immortalized mouse WT and SLC4a11 KO cell lines were incubated in DMEM with and without 0.5mM glutamine for 6 hours. In order to assess mitophagy, cells were stained using Lysotracker Red and Mitotracker Green. Colocalization co-efficients of red and green channels were obtained for at least 35 cells using Zeiss-Zen Pro software. Student’s t-test was used to determine statistical significance. For Western Blots, antibodies against LC3b, AMPK, pAMPK, and b-actin were used to examine autophagy flux and potential signaling pathways that regulate autophagy. RESULTS/ANTICIPATED RESULTS: Results – In the presence of glutamine, the colocalization co-efficient of Lysotracker Red and Mitotracker Green channels was significantly increased in KO cells (0.74 ±0.18) relative to WT (0.58±0.20) with a p-value ≤0.0024. In the absence of glutamine, the colocalization co-efficient was reversed, for KO cells 0.54 ±0.14 and for WT cells 0.77±0.0.16 with a p-value ≤0.0001, suggesting increased mitophagy by glutamine in KO cells. Western Blots indicated that glutamine increased autophagy flux, as indicated by increased levels of LC3b following bafilomycin A treatment in KO cells. Concomitantly, there was an increase in pAMPK/AMPK levels suggesting a potential mechanism for increased mitophagy. DISCUSSION/SIGNIFICANCE OF IMPACT: Conclusion and Future studies –Our data indicates enhanced mitophagy as well as autophagy in SLC4a11 KO cells. Future studies will determine whether these processes regulate cell survival in mouse models of corneal endothelial dystrophies.
Omega-3 (ω-3) and social skills interventions for reactive aggression and childhood externalizing behavior problems: a randomized, stratified, double-blind, placebo-controlled, factorial trial
- Adrian Raine, Rebecca P. Ang, Olivia Choy, Joseph R. Hibbeln, Ringo M-H. Ho, Choon Guan Lim, Nikki S. J. Lim-Ashworth, Shichun Ling, Jean C. J. Liu, Yoon Phaik Ooi, Yi Ren Tan, Daniel S. S. Fung
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- Journal:
- Psychological Medicine / Volume 49 / Issue 2 / January 2019
- Published online by Cambridge University Press:
- 10 May 2018, pp. 335-344
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Background
While studies suggest that nutritional supplementation may reduce aggressive behavior in children, few have examined their effects on specific forms of aggression. This study tests the primary hypothesis that omega-3 (ω-3), both alone and in conjunction with social skills training, will have particular post-treatment efficacy for reducing childhood reactive aggression relative to baseline.
MethodsIn this randomized, double-blind, stratified, placebo-controlled, factorial trial, a clinical sample of 282 children with externalizing behavior aged 7–16 years was randomized into ω-3 only, social skills only, ω-3 + social skills, and placebo control groups. Treatment duration was 6 months. The primary outcome measure was reactive aggression collected at 0, 3, 6, 9, and 12 months, with antisocial behavior as a secondary outcome.
ResultsChildren in the ω-3-only group showed a short-term reduction (at 3 and 6 months) in self-report reactive aggression, and also a short-term reduction in overall antisocial behavior. Sensitivity analyses and a robustness check replicated significant interaction effects. Effect sizes (d) were small, ranging from 0.17 to 0.31.
ConclusionsFindings provide some initial support for the efficacy of ω-3 in reducing reactive aggression over and above standard care (medication and parent training), but yield only preliminary and limited support for the efficacy of ω-3 in reducing overall externalizing behavior in children. Future studies could test further whether ω-3 shows promise in reducing more reactive, impulsive forms of aggression.
The molecular choreography of protein synthesis: translational control, regulation, and pathways
- Jin Chen, Junhong Choi, Seán E. O'Leary, Arjun Prabhakar, Alexey Petrov, Rosslyn Grosely, Elisabetta Viani Puglisi, Joseph D. Puglisi
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- Quarterly Reviews of Biophysics / Volume 49 / 2016
- Published online by Cambridge University Press:
- 24 June 2016, e11
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Translation of proteins by the ribosome regulates gene expression, with recent results underscoring the importance of translational control. Misregulation of translation underlies many diseases, including cancer and many genetic diseases. Decades of biochemical and structural studies have delineated many of the mechanistic details in prokaryotic translation, and sketched the outlines of eukaryotic translation. However, translation may not proceed linearly through a single mechanistic pathway, but likely involves multiple pathways and branchpoints. The stochastic nature of biological processes would allow different pathways to occur during translation that are biased by the interaction of the ribosome with other translation factors, with many of the steps kinetically controlled. These multiple pathways and branchpoints are potential regulatory nexus, allowing gene expression to be tuned at the translational level. As research focus shifts toward eukaryotic translation, certain themes will be echoed from studies on prokaryotic translation. This review provides a general overview of the dynamic data related to prokaryotic and eukaryotic translation, in particular recent findings with single-molecule methods, complemented by biochemical, kinetic, and structural findings. We will underscore the importance of viewing the process through the viewpoints of regulation, translational control, and heterogeneous pathways.
Contributors
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- By Linda S. Aglio, Cyrus Ahmadi Yazdi, Syed Irfan Qasim Ali, Caryn Barnet, Jessica Bauerle, Felicity Billings, Evan Blaney, Beverly Chang, Christopher Chen, Zinaida Chepurny, Hyung Sun Choi, Allison Clark, Lauren J. Cornella, Lisa Crossley, Michael D’Ambra, Galina Davidyuk, Whitney de Luna, Manisha S. Desai, Sukumar P. Desai, Kelly G. Elterman, Michaela K. Farber, Iuliu Fat, Jaida Fitzgerald, Devon Flaherty, John A. Fox, Gyorgy Frendl, Rejean Gareau, Joseph M. Garfield, Andrea Girnius, Laverne D. Gugino, J. Tasker Gundy, Carly C. Guthrie, Lisa M. Hammond, M. Tariq Hanifi, James Hardy, Philip M. Hartigan, Thomas Hickey, Richard Hsu, Mohab Ibrahim, David Janfaza, Yuka Kiyota, Suzanne Klainer, Benjamin Kloesel, Hanjo Ko, Bhavani Kodali, Vesela Kovacheva, J. Matthew Kynes, Robert W. Lekowski, Joyce Lo, Jeffrey Lu, Alvaro A. Macias, Zahra M. Malik, Erich N. Marks, Brendan McGinn, Jonathan R. Meserve, Annette Mizuguchi, Srdjan S. Nedeljkovic, Ju-Mei Ng, Michael Nguyen, Olutoyin Okanlawon, Jennifer Oliver, Krishna Parekh, Jessica Patterson, Christian Peccora, Pete Pelletier, Sujatha Pentakota, James H. Philip, Marc Philip T. Pimentel, Timothy D. Quinn, Elizabeth M. Rickerson, Susan L. Sager, Julia Serber, Shaheen Shaikh, Stanton Shernan, David Silver, Alissa Sodickson, Pingping Song, George P. Topulos, Agnieszka Trzcinka, Richard D. Urman, Rosemary Uzomba, Joshua Vacanti, Assia Valovska, Michael Vaninetti, Scott W. Vaughan, Kamen Vlassakov, Christopher Voscopoulos, Emily L. Wang, Laura Westfall, Zhiling Xiong, Stephanie Yacoubian, Dongdong Yao, Martin Zammert, Maksim Zayaruzny, Jose Luis Zeballos, Natthasorn Zinboonyahgoon, Jie Zhou
- Edited by Linda S. Aglio, Robert W. Lekowski, Richard D. Urman
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- Essential Clinical Anesthesia Review
- Published online:
- 05 February 2015
- Print publication:
- 08 January 2015, pp xi-xvi
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- By Ted Abel, Antoine Adamantidis, Karla V. Allebrandt, Simon N. Archer, Amelie Baud, Michel Billiard, Carlos Blanco-Centurion, Diane B. Boivin, Ethan Buhr, Matthew E. Carter, Nicolas Cermakian, Jennifer H.K. Choi, S.Y. Christin Chong, Chiara Cirelli, Marc Cuesta, Thomas Curie, Yves Dauvilliers, Luis de Lecea, Derk-Jan Dijk, Stephane Dissel, Annette C. Fedson, Jonathan Flint, Marcos G. Frank, Paul Franken, Ying-Hui Fu, Thorarinn Gislason, David Gozal, Devon A. Grant, Hakon Hakonarson, Makoto Honda, Hyun Hor, Christer Hublin, Peng Jiang, Takashi Kanbayashi, Jaakko Kaprio, Andrew Kasarskis, Leila Kheirandish-Gozal, RodaRani Konadhode, Michael Lazarus, Meng Liu, Michael March, Mark F. Mehler, Keivan Kaveh Moghadam, Valérie Mongrain, Charles M. Morin, Benjamin M. Neale, Seiji Nishino, Allan I. Pack, Dheeraj Pelluru, Rosa Peraita-Adrados, Giuseppe Plazzi, David A. Prober, Louis J. Ptáček, Irfan A. Qureshi, David M. Raizen, John J. Renger, Till Roenneberg, Elizabeth J. Rossin, Takeshi Sakurai, Paul Salin, Karen D. Schilli, Eva C. Schulte, Laurent Seugnet, Paul J. Shaw, Priyattam J. Shiromani, Patrick Sleiman, Mehdi Tafti, Joseph S. Takahashi, Matthew S. Thimgan, Katsushi Tokunaga, Giulio Tononi, Fred W. Turek, Yoshihiro Urade, Hans P.A. Van Dongen, Juliane Winkelmann, Christopher J. Winrow
- Edited by Paul Shaw, Mehdi Tafti, Michael J. Thorpy
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- The Genetic Basis of Sleep and Sleep Disorders
- Published online:
- 05 November 2013
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- 24 October 2013, pp xi-xiv
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. Nicholson, George W. E. Nickelsburg, Tatyana Nikolskaya, Damayanthi M. A. Niles, Bertil Nilsson, Nyambura Njoroge, Fidelis Nkomazana, Mary Beth Norton, Christian Nottmeier, Sonene Nyawo, Anthère Nzabatsinda, Edward T. Oakes, Gerald O'Collins, Daniel O'Connell, David W. Odell-Scott, Mercy Amba Oduyoye, Kathleen O'Grady, Oyeronke Olajubu, Thomas O'Loughlin, Dennis T. Olson, J. Steven O'Malley, Cephas N. Omenyo, Muriel Orevillo-Montenegro, César Augusto Ornellas Ramos, Agbonkhianmeghe E. Orobator, Kenan B. Osborne, Carolyn Osiek, Javier Otaola Montagne, Douglas F. Ottati, Anna May Say Pa, Irina Paert, Jerry G. Pankhurst, Aristotle Papanikolaou, Samuele F. Pardini, Stefano Parenti, Peter Paris, Sung Bae Park, Cristián G. Parker, Raquel Pastor, Joseph Pathrapankal, Daniel Patte, W. Brown Patterson, Clive Pearson, Keith F. Pecklers, Nancy Cardoso Pereira, David Horace Perkins, Pheme Perkins, Edward N. Peters, Rebecca Todd Peters, Bishop Yeznik Petrossian, Raymond Pfister, Peter C. Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. Van Bavel, Steven Vanderputten, Peter Van der Veer, Huub Van de Sandt, Louis Van Tongeren, Luke A. Veronis, Noel Villalba, Ramón Vinke, Tim Vivian, David Voas, Elena Volkova, Katharina von Kellenbach, Elina Vuola, Timothy Wadkins, Elaine M. Wainwright, Randi Jones Walker, Dewey D. Wallace, Jerry Walls, Michael J. Walsh, Philip Walters, Janet Walton, Jonathan L. Walton, Wang Xiaochao, Patricia A. Ward, David Harrington Watt, Herold D. Weiss, Laurence L. Welborn, Sharon D. Welch, Timothy Wengert, Traci C. West, Merold Westphal, David Wetherell, Barbara Wheeler, Carolinne White, Jean-Paul Wiest, Frans Wijsen, Terry L. Wilder, Felix Wilfred, Rebecca Wilkin, Daniel H. Williams, D. Newell Williams, Michael A. Williams, Vincent L. Wimbush, Gabriele Winkler, Anders Winroth, Lauri Emílio Wirth, James A. Wiseman, Ebba Witt-Brattström, Teofil Wojciechowski, John Wolffe, Kenman L. Wong, Wong Wai Ching, Linda Woodhead, Wendy M. Wright, Rose Wu, Keith E. Yandell, Gale A. Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- Book:
- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Contributors
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- By Deborah Abeles, Adrian Alvarez, Euler Ázaro, Paulo Batista, Donald P. Bernstein, Jay B. Brodsky, Kathleen Carey, Venita Chandra, Jenny Choi, Maria L. Collazo-Clavell, Jeremy Collins, Eric J. DeMaria, Galina Dimirova, Sanjeev Dutta, João Ettinger, Ronald Harter, Matthew M. Hutter, Jerry Ingrande, Daniel B. Jones, Stephanie B. Jones, Helen Karakelides, Fawzi S. Khayat, Hendrikus J. M. Lemmens, Yigal Leykin, Amy Lightner, Masha Livhits, Melinda A. Maggard, Tracy Martinez, John M. Morton, Patrick J. Neligan, Ninh T. Nguyen, Alfons Pomp, Silvia E. Perez-Protto, Steve E. Raper, Roman Schumann, Scott A. Shikora, Ashish Sinha, Brian R. Smith, Juraj Sprung, Pedro P. Tanaka, Brandon Tari, David O. Warner, Toby N. Weingarten, Joseph G. Werner, Gavitt A. Woodard, Basil M. Yurcisin, David Zvara
- Edited by Adrian Alvarez, Jay B. Brodsky, Stanford University School of Medicine, California, Hendrikus J. M. Lemmens, Stanford University School of Medicine, California, John M. Morton, Stanford University School of Medicine, California
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- Morbid Obesity
- Published online:
- 04 May 2010
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- 11 March 2010, pp -
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Theoretical and Experimental Study of Tip Electronic Structure in Scanning Tunneling Microscope
- HeeSung Choi, Min Huang, Joshua B Ballard, Kevin T He, Scott W Schmucker, Joseph N Lyding, John N Randall, Kyeongjae Cho
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1177 / 2009
- Published online by Cambridge University Press:
- 31 January 2011, 1177-Z06-03
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- 2009
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The atomic and electronic structures of pyramidal model STM tips of transition metals (W, Rh, Pd, Ir and Pt) were investigated using density functional theory (DFT) method. The calculated density of states show that d electrons of the apex atoms in the M4 (M = W, Rh, Pd, Ir, Pt) model tips behave differently near the Fermi level, with the dz2 state being dominant only for W tip. The electronic structures of pyramid structures of W and Pd single-atom tips with larger sizes are studied and compared. The density of states of Pd apex atom and W apex atom show different occupation of d-bands leading to asymmetric density of states for Pd tip. The asymmetric tunneling currents measured by W and Pt-Ir STM tips are explained by the calculated electronic structures of W and Pd model tips.
From Process Assumptions to Development to Manufacturing
- Theo Standaert, Allen Gabor, Andrew Simon, Anthony Lisi, Carsten Peters, Craig Child, Dimitri Kioussis, Edward Engbrecht, Fen Chen, Frieder Baumann, Gerhard Lembach, Hermann Wendt, Jihong Choi, Joseph Linville, Kaushik Chanda, Kaushik Kumar, Kenneth Davis, Laertis Economikos, Lee Nicholson, Moosung Chae, Naftali Lustig, Oscar Bravo, Paul McLaughlin, Ravi Prakash Srivastava, Ronald Filippi, Sujatha Sankaran, Tibor Bolom, Vinayan Menon, Vincent McGahay, Wai-Kin Li, Wei-Tsu Tseng, William Landers, Youngjin Choi, Glenn Biery, Thom Gow
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1079 / 2008
- Published online by Cambridge University Press:
- 01 February 2011, 1079-N02-01
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- 2008
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A tool has been developed that can be used to characterize or validate a BEOL interconnect technology. It connects various process assumptions directly to electrical parameters including resistance. The resistance of narrow copper lines is becoming a challenging parameter, not only in terms of controlling its value but also understanding the underlying mechanisms. The resistance was measured for 45nm-node interconnects and compared to the theory of electron scattering. This work will demonstrate how valuable it is to directly link the electrical models to the physical on-wafer dimensions and in turn to the process assumptions. For example, one can generate a tolerance pareto for physical and or electrical parameters that immediately identifies those process sectors that have the largest contribution to the overall tolerance. It also can be used to easily generate resistance versus capacitance plots which provide a good BEOL performance gauge. Several examples for 45nm BEOL will be given to demonstrate the value of these tools.
The Electrical Characterization of Molecular-Beam-Deposited LaAlO3 on GaAs and its Annealing Effects
- Donghun Choi, Maitri Warusawithana, Chi On Chui, Joseph Chen, Wilman Tsai, Darrell G. Schlom, James S. Harris
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- Journal:
- MRS Online Proceedings Library Archive / Volume 996 / 2007
- Published online by Cambridge University Press:
- 01 February 2011, 0996-H05-31
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- 2007
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The electrical properties of Al/LaAlO3/GaAs metal-oxide-semiconductor capacitors were investigated. A thick arsenic (As2) capping layer was used to protect the GaAs from oxidation and contamination during the air exposure that occurred between the deposition of the GaAs and LaAlO3 layers in different molecular-beam epitaxy systems. Amorphous LaAlO3 was deposited on c(4×4)- and (2×4)-reconstructed (100) GaAs surfaces. Post dielectric deposition annealing was found to improve the capacitance-voltage (C-V) characteristics by eliminating frequency dispersion in the depletion and weak inversion regimes and diminished the bi-directional C-V hysteresis to 210 mV. Reasonably low gate leakage current was maintained after annealing.
Early phase trials of minocycline in amyotrophic lateral sclerosis
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- By Paul H. Gordon, Department of Neurology, Columbia University, NY, USA; Email: phg8@columbia.edu, Joseph Choi, Department of Neurology, Columbia University, NY, USA; Email: phg8@columbia.edu, Dan H. Moore, Department of Biostatistics, California Pacific Medical Center, CA, USA; Email: dmoore@cc.UCSF.edu, Robert G. Miller, Department of Neurology, California Pacific Medical Center, CA, USA; Email: millerrx@sutterhealth.org
- Edited by Jeffrey L. Cummings
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- Book:
- Progress in Neurotherapeutics and Neuropsychopharmacology
- Published online:
- 22 March 2010
- Print publication:
- 06 April 2006, pp 63-78
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Summary
Key words: amyotrophic lateral sclerosis; minocycline; clinical trial; neurodegeneration.
Introduction and Overview
Amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by selective motor neuron cell death, leads to progressive weakness and death in an average of 3 years (Rowland & Shneider, 2001). There is no cure or known treatment that improves function. The mechanisms of motor neuron degeneration are not fully understood, but there is evidence that mitochondrial dysfunction, free radical toxicity, glutamate excitotoxicity, and intermediate filament-aggregation lead to activation of genes and enzymes that control cell death pathways, including apoptosis (Martin, 1999; Wiedemann et al., 1998; Rothstein et al., 1992; Hirano, 1991). Up-regulation of stress enzymes such as p38 mitogen activated protein (MAP) kinase and release of mitochondrial cytochrome c may contribute to activation of pro-inflammatory and pro-apoptotic modulators (Zhu et al., 2002; Mota et al., 2001; Horstmann et al., 1998; Migheli et al., 1997; Schiffer et al., 1996). Inflammatory cells and cytokines, including inducible nitric oxide synthase (iNOS), components of the complement cascade, and pro-apoptotic caspase enzymes are activated in areas of neurodegeneration in ALS (Almer et al., 2001; Li et al., 2000; Martin et al., 2000; Kostic et al., 1997). Caspase enzyme inhibitors and anti-inflammatory agents slow progression in the transgenic mouse model of ALS (Drachman et al., 2002; Barneoud and Curet, 2000; Friedlander et al., 1997).
Minocycline, which has both anti-inflammatory and anti-apoptotic properties, crosses the blood–brain barrier, and has been shown to have neuroprotective effects in models of ALS and other neurodegenerative disorders.
A High-Performance Corrosion-Resistant Iron-Based Amorphous Metal - The Effects of Composition, Structure and Environment on Corrosion Resistance
- Joseph Collin Farmer, J. Haslam, D. Day, T. Lian, C. Saw, P. Hailey, J-S. Choi, R. Rebak, N. Yang, R. Bayles, L. Aprigliano, J. Payer, J. Perepezko, K. Hildal, E. Lavernia, L. Ajdelsztajn, D. Branagan, B. Beardsley
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- Journal:
- MRS Online Proceedings Library Archive / Volume 985 / 2006
- Published online by Cambridge University Press:
- 19 October 2011, 0985-NN08-03
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- 2006
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The passive film stability of several Fe-based amorphous metal formulations have been found to be comparable to that of high-performance Ni-based alloys, and superior to that of stainless steels, based on electrochemical measurements of the passive film breakdown potential and general corrosion rates. Chromium (Cr), molybdenum (Mo) and tungsten (W) provide corrosion resistance; boron (B) enables glass formation; and rare earths such as yttrium (Y) lower critical cooling rate (CCR). The high boron content of this particular amorphous metal also makes it an effective neutron absorber, and suitable for criticality control applications, as discussed in companion publications. Corrosion data for SAM2X5 (Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4) is discussed here.
Application of Neutron-Absorbing Structural-Amorphous Metal (SAM) Coatings for Spent Nuclear Fuel (SNF) Container to Enhance Criticality Safety Controls
- Jor-Shan Choi, Chuck Lee, Joseph Farmer, Dan Day, Mark Wall, Cheng Saw, Moe Boussoufi, Ben Liu, Halold Egbert, Dan Branagan, Andy D'Amato
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- Journal:
- MRS Online Proceedings Library Archive / Volume 985 / 2006
- Published online by Cambridge University Press:
- 19 October 2011, 0985-NN08-02
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- 2006
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Spent nuclear fuel contains fissionable materials (235U, 239Pu, 241Pu, etc.). To prevent nuclear criticality in spent fuel storage, transportation, and during disposal, neutron-absorbing materials (or neutron poisons, such as borated stainless steel, Boral™, Metamic™, Ni-Gd, and others) would have to be applied. The success in demonstrating that the High-Performance Corrosion-Resistant Material (HPCRM) can be thermally applied as coating onto base metal to provide for corrosion resistance for many naval applications raises the interest in applying the HPCRM to USDOE/OCRWM spent fuel management program. The fact that the HPCRM relies on the high content of boron to make the material amorphous – an essential property for corrosion resistance – and that the boron has to be homogenously distributed in the HPCRM qualify the material to be a neutron poison.
Comparative Study on the Corrosion Resistance of Fe-Based Amorphous Metal, Borated Stainless Steel and Ni-Cr-Mo-Gd Alloy
- Tiangan Lian, Daniel Day, Phillip Hailey, Jor-Shan Choi, Joseph Farmer
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- Journal:
- MRS Online Proceedings Library Archive / Volume 985 / 2006
- Published online by Cambridge University Press:
- 19 October 2011, 0985-NN08-07
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- 2006
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Iron-based amorphous alloy Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 was compared to borated stainless steel and Ni-Cr-Mo-Gd alloy on their corrosion resistance in various high-[Cl-] solutions. The melt-spun ribbon of this iron-based amorphous alloy have demonstrated a better corrosion resistance than the bulk borated stainless steel and the bulk Ni-Cr-Mo-Gd alloy, in high-[Cl-] brines at temperatures 90ºC or higher.
Early Phase Trials of Minocycline in Amyotrophic Lateral Sclerosis
- Paul H. Gordon, Joseph Choi, Dan H. Moore, Robert G. Miller
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- Journal:
- Progress in Neurotherapeutics and Neuropsychopharmacology / Volume 1 / Issue 1 / January 2006
- Published online by Cambridge University Press:
- 15 February 2006, pp. 63-77
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- January 2006
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Drag reduction by polymer additives in a turbulent channel flow
- TAEGEE MIN, JUNG YUL YOO, HAECHEON CHOI, DANIEL D. JOSEPH
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- Journal:
- Journal of Fluid Mechanics / Volume 486 / 10 June 2003
- Published online by Cambridge University Press:
- 24 June 2003, pp. 213-238
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Turbulent drag reduction by polymer additives in a channel is investigated using direct numerical simulation. The dilute polymer solution is expressed with an Oldroyd-B model that shows a linear elastic behaviour. Simulations are carried out by changing the Weissenberg number at the Reynolds numbers of 4000 and 20 000 based on the bulk velocity and channel height. The onset criterion for drag reduction predicted in the present study shows a good agreement with previous theoretical and experimental studies. In addition, the flow statistics such as the r.m.s. velocity fluctuations are also in good agreement with previous experimental observations. The onset mechanism of drag reduction is interpreted based on elastic theory, which is one of the most plausible hypotheses suggested in the past. The transport equations for the kinetic and elastic energy are derived for the first time. It is observed that the polymer stores the elastic energy from the flow very near the wall and then releases it there when the relaxation time is short, showing no drag reduction. However, when the relaxation time is long enough, the elastic energy stored in the very near-wall region is transported to and released in the buffer and log layers, showing a significant amount of drag reduction.
Disposable Smart Plastic Biochips For Clinical Diagnostics
- Chong H. Ahn, Jin-Woo Choi, Sanghyo Kim, Young-Soo Sohn, Aniruddha Puntambekar, Suresh Murugesan, Gregory Beaucage, Joseph H. Nevin
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- Journal:
- MRS Online Proceedings Library Archive / Volume 729 / 2002
- Published online by Cambridge University Press:
- 01 February 2011, U1.8
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- 2002
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This paper presents an overview of the development of novel disposable smart plastic fluidic biochips for clinical diagnostic applications. The biochip is manufactured using a low-cost, rapid turn around injection molding/embossing process on a plastic substrate. The plastic fluidic biochip uses a novel sPROMs (structurally programmable microfluidic system) approach to achieve passive control of fluidic sequencing [1-2]. The plastic biochip also uses an on-chip pressurized air source for fluidic movement thus eliminating the need for active driving mechanisms and allowing for a truly disposable approach. Furthermore, electrochemical biosensors are also integrated on-chip to analyze various metabolically significant parameters such as PO2(partial pressure of oxygen), Glucose, Lactate,and pH. The fluidic biochip is being developed for point-of-care health monitoring applications where parameters such as small size, simplicity of operation, disposability, reduced cross-contamination are vital. The issues mentioned above are successfully addressed using the approach of this work and are discussed in this paper.
A correlation for the lift-off of many particles in plane Poiseuille flows of Newtonian fluids
- N. A. PATANKAR, T. KO, H. G. CHOI, D. D. JOSEPH
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- Journal:
- Journal of Fluid Mechanics / Volume 445 / 25 October 2001
- Published online by Cambridge University Press:
- 16 October 2001, pp. 55-76
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Choi & Joseph (2001) reported a two-dimensional numerical investigation of the lift-off of 300 circular particles in plane Poiseuille flows of Newtonian fluids. We perform similar simulations. Particles heavier than the fluid are initially placed in a closely packed ordered configuration at the bottom of a periodic channel. The fluid–particle mixture is driven by an external pressure gradient. The particles are suspended or fluidized by lift forces that balance the buoyant weight perpendicular to the flow. Pressure waves corresponding to the waves at the fluid–mixture interface are observed. During the initial transient, these waves grow, resulting in bed erosion. At sufficiently large shear Reynolds numbers the particles occupy the entire channel width during the transient. The particle bed eventually settles to an equilibrium height which increases as the shear Reynolds number is increased. Heavier particles are lifted to a smaller equilibrium height at the same Reynolds number. A correlation for the lift-off of many particles is obtained from the numerical data. The correlation is used to estimate the critical shear Reynolds number for lift-off of many particles. The critical shear Reynolds number for lift-off of a single particle is found to be greater than that for many particles. The procedures used here to obtain correlations from direct simulations in two dimensions and the type of correlations that emerge should generalize to three-dimensional simulations at present underway.
Fluidization by lift of 300 circular particles in plane Poiseuille flow by direct numerical simulation
- HYOUNG G. CHOI, DANIEL D. JOSEPH
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- Journal:
- Journal of Fluid Mechanics / Volume 438 / 10 July 2001
- Published online by Cambridge University Press:
- 05 July 2001, pp. 101-128
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We study the transport of a slurry of heavier-than-liquid circular particles in a plane pressure-driven flow in a direct simulation. The flow is calculated in a periodic domain containing 300 circular particles. The study leads to the concept of fluidization by lift in which all the particles are suspended by lift forces against gravity perpendicular to the flow. The study is framed as an initial-value problem in which a closely packed cubic array of particles resting on the bottom of the channel is lifted into suspension. All the details of the flow are resolved numerically without model assumptions. The fluidization of circular particles first involves bed inflation in which liquid is driven into the bed by high pressure at the front and low pressure at the back of each circle in the top row. This kind of bed inflation occurs even at very low Reynolds numbers but it takes more time for the bed to inflate as the Reynolds number is reduced. It appears that the bed will not inflate if the shear Reynolds number is below the critical value for single particle lift-off. The flows with a single particle are completely determined by a shear Reynolds number and a gravity parameter when the density ratio and aspect ratio parameters are specified. In the multi-particle case, the volume fraction and distribution also matters. The transition to a fully fluidized slurry by waves is discussed.
An analytical model of the steady motion of a single particle dragged forward in a Poiseuille flow is derived and compared with a simulation. The undisturbed fluid velocity is always larger than the particle velocity, producing a fluid hold-up. The effect of the hold-up in the many particle case is to greatly reduce the velocity of the mixture which may be described by a two-fluid model in which the solid laden mixture is regarded as a second fluid with effective properties.