36 results
418 Activation of the Glucagon-Like Peptide-1 Pathway in Obese Pre-Diabetic Individuals Improves Endothelial Function Independently of Weight Loss
- Mona Mashayekhi, Joshua A. Beckman, Erica M. Garner, Hui Nian, Chang Yu, Sara E. Howard, Bradley Perkins, Jessica K. Devin, John R. Koethe, Jonathan D. Brown, Heidi Silver, James M. Luther, Nancy J. Brown
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- Journal:
- Journal of Clinical and Translational Science / Volume 6 / Issue s1 / April 2022
- Published online by Cambridge University Press:
- 19 April 2022, pp. 81-82
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OBJECTIVES/GOALS: We aimed to determine if GLP-1 receptor agonists exert beneficial effects on surrogate measures of cardiovascular function independently of weight loss. Our objective was to compare the outcomes between GLP-1 receptor agonist treatment versus a similar drug without cardiovascular benefit versus weight loss through diet alone. METHODS/STUDY POPULATION: We enrolled 88 individuals with obesity (BMI ≥ 30kg/m2) and pre-diabetes and randomized them in a 2:1:1 ratio to 14 weeks of the GLP-1 receptor agonist liraglutide, the dipeptidyl peptidase-4 inhibitor sitagliptin, or hypocaloric diet. Sitagliptin blocks degradation of endogenous GLP-1 but does not cause weight loss or lower adverse cardiovascular outcomes. Treatment was double-blinded and placebo-controlled for drug, and unblinded for diet. Primary endpoints were flow-mediated dilation (FMD) to assess endothelial vasodilatory function, and plasminogen activator inhibitor-1 (PAI-1) to assess endothelial fibrinolytic function. We used a general linear model for each outcome and included gender as a covariate for FMD. Baseline characteristics were similar. Mean age was 50, with 32% men and 13% black. RESULTS/ANTICIPATED RESULTS: At 14 weeks, diet and liraglutide caused weight loss (diet -4.3 ± 3.2 kg, P<0.01; liraglutide -2.7 ± 3.2, P<0.01), while sitagliptin did not (-0.7 ± 2.0, P=0.17). Diet did not improve FMD at 14 weeks compared to baseline (+0.9%, 95% CI [-1.5, 3.3], P=0.46). FMD tended to increase after liraglutide and sitagliptin but was not significant (liraglutide +1.2 [-0.3, 2.8], P=0.12; sitagliptin +1.6 [-0.6, 3.8], P=0.15). Given that liraglutide and sitagliptin work through the same GLP-1 pathway, we combined the liraglutide and sitagliptin groups for overall effect on FMD, which was significantly improved from baseline (+1.4 [0.1, 2.8], P=0.04). Diet and liraglutide improved PAI-1 at 14 weeks (diet -4.4U/mL, [-8.5, -0.2], P=0.04; liraglutide -3.4 [-6.0, -0.7], P=0.01), while sitagliptin did not (-1.4 [-5.1, 2.3], P=0.46). DISCUSSION/SIGNIFICANCE: Activation of the GLP-1 pathway by liraglutide or sitagliptin improves FMD independent of weight loss, while PAI-1 improvement is weight-loss dependent and is only seen after liraglutide or diet. Our study suggests the cardiovascular benefit of liraglutide may be due to combined improvements in endothelial vasodilatory and fibrinolytic function.
Vortex shedding frequency in open-channel lateral cavity
- C. Perrot-Minot, E. Mignot, R. Perkins, D. Lopez, N. Riviere
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- Journal:
- Journal of Fluid Mechanics / Volume 892 / 10 June 2020
- Published online by Cambridge University Press:
- 06 April 2020, A25
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This article aims at predicting the oscillation frequency of open-channel lateral cavities, which are common sheltered zones of riverine environments, and have important ecological impact. Using a theoretical analysis based on an existing model for acoustic cavities and a free-surface lateral cavity experiment, we show that the vortex shedding in the mixing layer between the cavity and the open channel is always constrained by gravity waves even for low Froude numbers ($F<0.6$). This expands previous results from the literature showing the impact of gravity waves on the vortex shedding frequency for high Froude number ($F>0.6$). Measurements of the free-surface oscillation and transverse velocity oscillation frequencies reveal a unique frequency along the mixing layer, equal to the free-surface oscillation frequency anywhere in the cavity. Hence, it is shown that the vortex shedding frequency in an open-channel lateral cavity always equals a match between a natural frequency of the cavity and a solution of the feedback model developed herein for low to moderate Froude numbers.
An experimental investigation of the laminar horseshoe vortex around an emerging obstacle
- Gaby Launay, E. Mignot, N. Riviere, R. Perkins
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- Journal of Fluid Mechanics / Volume 830 / 10 November 2017
- Published online by Cambridge University Press:
- 29 September 2017, pp. 257-299
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An emerging long obstacle placed in a boundary layer developing under a free surface generates a complex horseshoe vortex (HSV) system, which is composed of a set of vortices exhibiting a rich variety of dynamics. The present experimental study examines such flow structure and characterizes precisely, using particle image velocimetry (PIV) measurements, the evolution of the HSV geometrical and dynamical properties over a wide range of dimensionless parameters (Reynolds number $Re_{h}\in [750,8300]$ , boundary layer development ratio $h/\unicode[STIX]{x1D6FF}\in [1.25,4.25]$ and obstacle aspect ratio $W/h\in [0.67,2.33]$ ). The dynamical study of the HSV is based on the categorization of the motions of HSV vortices that result in an enhanced specific bi-dimensional typology, separating a coherent (due to vortex–vortex interactions) and an irregular evolution (due to the appearance of small-scale instabilities). This precise categorization is made possible thanks to the use of vortex tracking methods applied to PIV measurements; a semi-empirical model for the motion of the HSV vortices is then proposed to highlight some important mechanisms of the HSV dynamics, such as (i) the influence of the surrounding vortices on vortex motion and (ii) the presence of a phase shift between the motion of all vortices. Finally, the study of the HSV’s geometrical properties (vortex position and characteristic lengths and frequencies) evolution with the flow parameters shows that strong dependencies exist between the streamwise extension of the HSV and the obstacle width, and between the HSV vortex number and its elongation. Comparison of these data with prior studies for immersed obstacles reveals that emerging obstacles lead to greater adverse pressure gradients and down-flows in front of the obstacle. This implies a precocious separation of the boundary layer, leading to a larger HSV streamwise extension, and a lower vertical extension of the HSV, leading to smaller HSV vortices.
Household water insecurity, missed schooling, and the mediating role of caregiver depression in rural Uganda
- C. E. Cooper-Vince, B. Kakuhikire, D. Vorechovska, A. Q. McDonough, J. Perkins, A. S. Venkataramani, R. C. Mushavi, C. Baguma, S. Ashaba, D. R. Bangsberg, A. C. Tsai
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- Journal:
- Global Mental Health / Volume 4 / 2017
- Published online by Cambridge University Press:
- 15 August 2017, e15
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Background
School attendance rates in sub-Saharan Africa are among the lowest worldwide, placing children at heightened risk for poor educational and economic outcomes. One understudied risk factor for missed schooling is household water insecurity, which is linked to depression among women and may increase children's water-fetching burden at the expense of educational activities, particularly among children of depressed caregivers. In this study conducted in rural Uganda, we assessed the association between household water insecurity and child school participation and the mediating pathways behind these associations.
MethodWe conducted a population-based, cross-sectional study of female household heads (N = 257) and their children ages 5–17 (N = 551) in the rural regions surrounding the town of Mbarara, in southwestern Uganda. We used multivariable linear regressions to estimate the association between water insecurity and missed schooling. We then assessed the extent to which the association was mediated by caregiver depression.
ResultsAmong children, water insecurity had a statistically significant association with the number of missed school days (a standard deviation increase in water insecurity resulted in 0.30 more missed school days in the last week). The estimated association was partially mediated by caregiver depression. When stratified by sex, this mediating pathway remained significant for boys, but not among girls.
ConclusionsWater insecurity is a risk factor for missed schooling among children in rural Uganda. Caregiver depression partially mediated this relationship. Also addressing caregiver mental health in water insecure families may more fully address the needs of sub-Saharan African families and promote educational participation among youth.
P091: Anaphylaxis: epidemiology and treatment in a Canadian emergency department
- J. Morris, A. Marcotte, S. La Vieille, R. Alizadehfar, E. Perkins, A. Clarke, M. Ben-Shoshan
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- Journal:
- Canadian Journal of Emergency Medicine / Volume 18 / Issue S1 / May 2016
- Published online by Cambridge University Press:
- 02 June 2016, pp. S108-S109
- Print publication:
- May 2016
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Introduction: As part of the multicenter C-CARE (Cross-Canada Anaphylaxis Registry) project, this study aimed to describe the characteristics of anaphylactic reactions and assess if emergency physicians follow treatment guidelines. Methods: A cohort study was conducted in the emergency department of Sacré-Cœur Hospital, a university-affiliated, urban tertiary care hospital. For each anaphylaxis case recruited by the treating physician, a standardised questionnaire was completed. The information for missed cases was collected retrospectively through chart review. Results: Between May 2012 and May 2015, 280 cases (205 prospective and 75 retrospective) of anaphylaxis were identified from a total of 182,408 ED visits. The median age was 36.21 years (IQR 27.8), 61.8% were female, and 12.5% of all patients were children (<18 years old). The majority of reactions were triggered by food [54.3% (95%CI:48.5-60.1%)], followed by medications [18.2% (95%CI:13.7-22.7%)] and venom [5.7% (95%CI:3.0-8.4%)]. Among all cases, 66.8% (95%CI:61.3-72.3%) received epinephrine; 26.1% (95%CI:21.0-31.2%) received it prior to their arrival and 46.8% (95%CI:41.0-52.6%) in-hospital. As for other in-hospital treatments, 85.4% of patients (95%CI:81.3-89.5%) received corticosteroids, 81.1% (95%CI:76.5-85.7%) received H1 antihistamines, and 41.1% (95%CI:35.3-46.9%) received H2 antihistamines. Out of all patients who had anaphylaxis, 86.4% (95%CI:82.4-90.4%) were prescribed an epinephrine auto-injector in-hospital or had already had one prescribed. Conclusion: Our results reveal that food is a major trigger of anaphylaxis and that despite current guidelines, there is under use of epinephrine and preferential use of corticosteroids and antihistamines.
Substance use in individuals at clinical high risk of psychosis
- L. Buchy, K. S. Cadenhead, T. D. Cannon, B. A. Cornblatt, T. H. McGlashan, D. O. Perkins, L. J. Seidman, M. T. Tsuang, E. F. Walker, S. W. Woods, R. Heinssen, C. E. Bearden, D. Mathalon, J. Addington
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- Journal:
- Psychological Medicine / Volume 45 / Issue 11 / August 2015
- Published online by Cambridge University Press:
- 02 March 2015, pp. 2275-2284
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Background
A series of research reports has indicated that the use of substances such as cannabis, alcohol and tobacco are higher in youth at clinical high risk (CHR) of developing psychosis than in controls. Little is known about the longitudinal trajectory of substance use, and findings on the relationship between substance use and later transition to psychosis in CHR individuals are mixed.
MethodAt baseline and 6- and 12-month follow-ups, 735 CHR and 278 control participants completed the Alcohol and Drug Use Scale and a cannabis use questionnaire. The longitudinal trajectory of substance use was evaluated with linear mixed models.
ResultsCHR participants endorsed significantly higher cannabis and tobacco use severity, and lower alcohol use severity, at baseline and over a 1-year period compared with controls. CHR youth had higher lifetime prevalence and frequency of cannabis, and were significantly younger upon first use, and were more likely to use alone and during the day. Baseline substance use did not differentiate participants who later transitioned to psychosis (n = 90) from those who did not transition (n = 272). Controls had lower tobacco use than CHR participants with a prodromal progression clinical outcome and lower cannabis use than those with a psychotic clinical outcome at the 2-year assessment.
ConclusionsIn CHR individuals cannabis and tobacco use is higher than in controls and this pattern persists across 1 year. Evaluation of clinical outcome may provide additional information on the longitudinal impact of substance use that cannot be detected through evaluation of transition/non-transition to psychosis alone.
M13 Bacteriophage Biolaminates for Nanomaterials with Improved Stiffness
- Christopher M. Warner, Amitabh Ghoshal, Michael F. Cuddy, Aimee R. Poda, Natalie D. Barker, Daniel E. Morse, Seung-Wuk Lee, Edward J. Perkins
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1722 / 2015
- Published online by Cambridge University Press:
- 16 June 2015, mrsf14-1722-f11-03
- Print publication:
- 2015
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In nature, biomolecules guide the formation of hierarchically-ordered, lightweight, inorganic-organic composites such as corals, shells, teeth and bones. M13 bacteriophage has been used to mimic bio-inspired material development due to its rigid, nanoscale rod-like morphology. Liquid-crystalline monolayers of genetically engineered phage have been used to template crystallization of thin layers of inorganic and metallic materials. We have created thin films composed of engineered M13 phage capable of binding inorganic components. We employed both a dip-cast and a drop-cast film fabrication method on both smooth and rough gold, silica and glass casting surfaces to create thin films and 3D structures of various degrees of hierarchical order. We have found the engineered M13 phage and the inorganic mineral significantly affected both film morphology and the mechanical properties of the film. Similarly, film fabrication parameters such as solution chemistry, temperature, and pulling speed affected film properties. Using a calcium phosphate biomineralized 4E phage, film thickness increased linearly with the number of layers/dips in the phage solution. The stiffness of these composites (Young's modulus) were >80 GPa for mineralized, multilayer films. These materials are an order of magnitude stiffer than the biological equivalent collagen. Stiffness, however, does not appear to increase in a multilayer film beyond a saturation point. Ultimately, we have developed a platform for phage-based bio-composites for developing high performance materials.
Biological Effects–Based Tools for Monitoring Impacted Surface Waters in the Great Lakes: A Multiagency Program in Support of the Great Lakes Restoration Initiative
- Drew R. Ekman, Gerald T. Ankley, Vicki S. Blazer, Timothy W. Collette, Natàlia Garcia-Reyero, Luke R. Iwanowicz, Zachary G. Jorgenson, Kathy E. Lee, Pat M. Mazik, David H. Miller, Edward J. Perkins, Edwin T. Smith, Joseph E. Tietge, Daniel L. Villeneuve
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- Journal:
- Environmental Practice / Volume 15 / Issue 4 / December 2013
- Published online by Cambridge University Press:
- 21 January 2014, pp. 409-426
- Print publication:
- December 2013
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There is increasing demand for the implementation of effects-based monitoring and surveillance (EBMS) approaches in the Great Lakes Basin to complement traditional chemical monitoring. Herein, we describe an ongoing multiagency effort to develop and implement EBMS tools, particularly with regard to monitoring potentially toxic chemicals and assessing Areas of Concern (AOCs), as envisioned by the Great Lakes Restoration Initiative (GLRI). Our strategy includes use of both targeted and open-ended/discovery techniques, as appropriate to the amount of information available, to guide a priori end point and/or assay selection. Specifically, a combination of in vivo and in vitro tools is employed by using both wild and caged fish (in vivo), and a variety of receptor- and cell-based assays (in vitro). We employ a work flow that progressively emphasizes in vitro tools for long-term or high-intensity monitoring because of their greater practicality (e.g., lower cost, labor) and relying on in vivo assays for initial surveillance and verification. Our strategy takes advantage of the strengths of a diversity of tools, balancing the depth, breadth, and specificity of information they provide against their costs, transferability, and practicality. Finally, a series of illustrative scenarios is examined that align EBMS options with management goals to illustrate the adaptability and scaling of EBMS approaches and how they can be used in management decisions.
Environmental Practice 15:409–426 (2013)
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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Contributors
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- By Joanne R. Adler, David A. Alexander, Laurence Alison, Catherine C. Ayoub, Peter Banister, Anthony R. Beech, Amanda Biggs, Julian Boon, Adrian Bowers, Neil Brewer, Eric Broekaert, Paula Brough, Jennifer M. Brown, Kevin Browne, Elizabeth A. Campbell, David Canter, Michael Carlin, Shihning Chou, Martin A. Conway, Claire Cooke, David Cooke, Ilse Derluyn, Robert J. Edelmann, Vincent Egan, Tom Ellis, Marie Eyre, David P. Farrington, Seena Fazel, Daniel B. Fishman, Victoria Follette, Katarina Fritzon, Elizabeth Gilchrist, Nathan D. Gillard, Renée Gobeil, Agnieszka Golec de Zavala, Jane Goodman-Delahunty, Lynsey Gozna, Don Grubin, Gisli H. Gudjonsson, Helinä Häkkänen-Nyholm, Guy Hall, Nathan Hall, Roisin Hall, Sean Hammond, Leigh Harkins, Grant T. Harris, Camilla Herbert, Robert D. Hoge, Todd E. Hogue, Clive R. Hollin, Lorraine Hope, Miranda A. H. Horvath, Kevin Howells, Carol A. Ireland, Jane L. Ireland, Mark Kebbell, Michael King, Bruce D. Kirkcaldy, Heidi La Bash, Cara Laney, William R. Lindsay, Elizabeth F. Loftus, L. E. Marshall, W. L. Marshall, James McGuire, Neil McKeganey, T. M. McMillan, Mary McMurran, Joav Merrick, Becky Milne, Joanne M. Nadkarni, Claire Nee, M. D. O’Brien, William O’Donohue, Darragh O’Neill, Jane Palmer, Adria Pearson, Derek Perkins, Devon L. L. Polaschek, Louise E. Porter, Charlotte C. Powell, Graham E. Powell, Martine Powell, Christine Puckering, Ethel Quayle, Vernon L. Quinsey, Marnie E. Rice, Randall Richardson-Vejlgaard, Richard Rogers, Louis B Schlesinger, Carolyn Semmler, G. A. Serran, Ralph C. Serin, John L. Taylor, Max Taylor, Brian Thomas-Peter, Paul A. Tiffin, Graham Towl, Rosie Travers, Arlene Vetere, Graham Wagstaff, Helen Wakeling, Fiona Warren, Brandon C. Welsh, David Wexler, Margaret Wilson, Dan Yarmey, Susan Young
- Edited by Jennifer M. Brown, London School of Economics and Political Science, Elizabeth A. Campbell, University of Glasgow
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- The Cambridge Handbook of Forensic Psychology
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- 06 July 2010
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- 29 April 2010, pp xix-xxiii
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Pandemic (H1N1) 2009 virus outbreak in a school in London, April–May 2009: an observational study
- L. CALATAYUD, S. KURKELA, P. E. NEAVE, A. BROCK, S. PERKINS, M. ZUCKERMAN, M. SUDHANVA, A. BERMINGHAM, J. ELLIS, R. PEBODY, M. CATCHPOLE, R. HEATHCOCK, H. MAGUIRE
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- Journal:
- Epidemiology & Infection / Volume 138 / Issue 2 / February 2010
- Published online by Cambridge University Press:
- 20 November 2009, pp. 183-191
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On 29 April 2009, an imported case of pandemic (H1N1) 2009 virus infection was detected in a London school. As further cases, pupils and staff members were identified, school closure and mass prophylaxis were implemented. An observational descriptive study was conducted to provide an insight into the clinical presentation and transmission dynamics in this setting. Between 15 April and 15 May 2009, 91 symptomatic cases were identified: 33 were confirmed positive for pandemic (H1N1) 2009 virus infection; 57 were tested negative; in one the results were unavailable. Transmission occurred first within the school, and subsequently outside. Attack rates were 2% in pupils (15% in the 11–12 years age group) and 17% in household contacts. The predominant symptoms were fever (97%), respiratory symptoms (91%), and sore throat (79%). Limited spread in the school may have been due to a combination of school closure and mass prophylaxis. However, transmission continued through household contacts to other schools.
Contributors
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- By Nalini Vadivelu, Christian J. Whitney, Raymond S. Sinatra, M. Khurram Ghori, Yu-Fan (Robert) Zhang, Raymond S. Sinatra, Joshua Wellington, Yuan-Yi Chia, Francis J. Keefe, Jon McCormack, Ian Power, John Butterworth, P. M. Lavand’homme, M. F. De Kock, Bradley Urie, Oscar A. de Leon-Casasola, Frederick M. Perkins, Larry F. Chu, David Clark, Martin S. Angst, Cynthia M. Welchek, Lisa Mastrangelo, Raymond S. Sinatra, Richard Martinez, Scott S. Reuben, Asokumar Buvanendran, Raymond S. Sinatra, Pamela E Macintyre, Julia Coldrey, Daniel B. Maalouf, Spencer S. Liu, Susan Dabu-Bondoc, Samantha A. Franco, Raymond S. Sinatra, James Benonis, Jennifer Fortney, David Hardman, Gavin Martin, Holly Evans, Karen C. Nielsen, Marcy S. Tucker, Stephen M. Klein, Benjamin Sherman, Ikay Enu, Raymond S. Sinatra, James W. Heitz, Eugene R. Viscusi, Jonathan S. Jahr, Kofi N. Donkor, Raymond S. Sinatra, Manzo Suzuki, Johan Raeder, Vegard Dahl, Stefan Erceg, Keun Sam Chung, Kok-Yuen Ho, Tong J. Gan, Dermot R. Fitzgibbon, Paul Willoughby, Brian E. Harrington, Joseph Marino, Tariq M. Malik, Raymond S. Sinatra, Giorgio Ivani, Valeria Mossetti, Simona Italiano, Thomas M. Halaszynski, Nousheh Saidi, Javier Lopez, Kate Miller, Ferne Braveman, Jaya L. Varadarajan, Steven J. Weisman, Sukanya Mitra, Raymond S. Sinatra, Theodore J. Saclarides, Knox H. Todd, James R. Miner, Chris Pasero, Nancy Eksterowicz, Margo McCaffery, Leslie N. Schechter, Amr E. Abouleish, Govindaraj Ranganathan, Tee Yong Tan, Stephan A. Schug, Marie N. Hanna, Spencer S. Liu, Christopher L. Wu, Craig T. Hartrick, Garen Manvelian, Christine Miaskowski, Brian Durkin, Peter S. A. Glass
- Edited by Raymond S. Sinatra, Oscar A. de Leon-Cassasola, University of Rochester Medical Center, New York, Eugene R. Viscusi, Brian Ginsberg
- Foreword by Henry McQuay
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- Acute Pain Management
- Published online:
- 26 October 2009
- Print publication:
- 27 April 2009, pp vii-xii
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The influence of light and temperature interactions on a natural estuarine microphytobenthic assemblage
- E. C. Defew, R. G. Perkins, D. M. Paterson
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A natural microphytobenthic assemblage from the Eden Estuary, Scotland, was used to study the effect of temperature and irradiance on the sustainability and species composition of a natural transient biofilm. Three tidal tanks were maintained: tank 1 at 10 °C; tank 2 at 18 °C; and tank 3 at 26 °C. Within each tank, five cores were unshaded (350 μmol/m2 per s), five cores were semi-shaded (175 μmol/m2 per s), and five cores were shaded (70 μmol/m2 per s). Chlorophyll a increased in all treatments, but accumulated slower with increasing temperature. Surface diatom biomass of biofilms (as determined from measurements of minimum fluorescence, Fo15), grown at 10 °C and 18 °C was sustained above initial levels after 21 days, whilst biofilms grown at 26 °C suffered a severe loss of diatoms after 14 days, probably owing to nutrient limitation. Species richness and diversity of diatom assemblages illustrated a variety of responses to the temperature and light conditions. Diatoms at 10 °C acclimated to the different light levels by varying the ratios of diadinoxanthin: chlorophyll a, whilst at 18 °C the diatom species composition changed dramatically in response to shading. Ratios of zeaxanthin: chlorophyll a increased with increasing temperature, indicating an increase in cyanobacterial biomass at 26 °C after 21 days. Increased temperature significantly increased the maximum theoretical electron transport rate (rETRmax) in the short term (days), although light and temperature treatments did not affect the maximum light utilization coefficient (αrETR). Limitations of the fluorescence methodology used to study the resultant mixed community of benthic phototrophs is discussed. Diatom vertical migration in response to light, and an alteration of the main functional taxonomic group, has implications for the interpretation and value of fluorescence data.
Study of ZnTe:Cu/Metal Interfaces in CdS/CdTe Phovoltaic Solar Cells
- T. A. Gessert, C. L. Perkins, S. E. Asher, A. Duda, M. R. Young
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- Journal:
- MRS Online Proceedings Library Archive / Volume 796 / 2003
- Published online by Cambridge University Press:
- 01 February 2011, V4.2
- Print publication:
- 2003
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The present model for current transport at the CdTe/p-ZnTe:Cu/metal back contact assumes that the CdTe and ZnTe valence bands align, while current transport at a highly doped ZnTe and a metal interface proceeds by tunneling. To test part of this model, we have investigated the electrical and material properties of CdS/CdTe devices where the outer metal is either Ti or Ni. Our results show that differences in device series resistance are not linked simply to metal/ZnTe:Cu interfacial contact resistance, but that metallization-induced diffusion remains a more likely cause of significant performance distinctions.
Structure of AlN on Si (111) Deposited with Metal Organic Vapor Phase Epitaxy
- Eric Rehder, M. Zhou, L. Zhang, N. R. Perkins, S. E. Babcock, T. F. Kuech
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- Journal:
- Materials Research Society Internet Journal of Nitride Semiconductor Research / Volume 4 / Issue S1 / 1999
- Published online by Cambridge University Press:
- 13 June 2014, pp. 322-326
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- 1999
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The surface morphology and structure of AlN deposited by metal organic vapor phase epitaxy (MOVPE) on Si (111) at growth temperatures ranging from 825 to 1175°C was investigated. Transmission electron microscopy (TEM), reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS) techniques were used to study the resulting film structure. Growth at high temperatures but less than ∼1100°C, resulted in a wire texture with some degree of in-plane alignment with (0001)AlN/ /(111)Si, < 10 0>AlN//< 11>Si, and 110>AlN//<10>Si. Deposition at temperatures greater than 1100°C results in single crystal films consisting of domains 60 nm across with an aspect ratio near unity. Growth below1100°C leads to degraded crystal quality with the grains developing random rotational misalignments around the AlN [0001] axis. Growth at lower temperatures produces islands elongated along the [110] direction. At the growth temperature of 825°C, the aspect ratio of the islands increased to 3 and a width of 25 nm. Cross-sectional TEM reveals that these islands are faceted due to slow growth on the {1 01}planes.
Structure of Ain on Si (111) Deposited with Metal Organic Vapor Phase Epitaxy
- Eric Rehder, M. Zhou, L. Zhang, N. R. Perkins, S. E. Babcock, T. F. Kuech
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- Journal:
- MRS Online Proceedings Library Archive / Volume 537 / 1998
- Published online by Cambridge University Press:
- 15 February 2011, G3.56
- Print publication:
- 1998
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The surface morphology and structure of AIN deposited by metal organic vapor phase epitaxy (MOVPE) on Si (111) at growth temperatures ranging from 825 to 1175°C was investigated. Transmission electron microscopy (TEM), reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS) techniques were used to study the resulting film structure. Growth at high temperatures but less than ∼1100°C, resulted in a wire texture with some degree of in-plane alignment with (0001)AIN //(111)si, <1010>AIN //<211>si, and <1120>AIN. // <110>si. Deposition at temperatures greater than 1100°C results in single crystal films consisting of domains 60 nm across with an aspect ratio near unity. Growth below 1100°C leads to degraded crystal quality with the grains developing random rotational misalignments around the AIN [0001] axis. Growth at lower temperatures produces islands elongated along the [1120] direction. At the growth temperature of 825°C, the aspect ratio of the islands increased to 3 and a width of 25 nm. Cross -sectional TEM reveals that these islands are faceted due to slow growth on the {1101} planes.
The Effect of Growth Temperature On The Microstructure of Movpe AlN/Si (111)
- Mei Zhou, N. R. Perkins, E. Rehder, T. F. Kuech, S. E. Babcock
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- Journal:
- MRS Online Proceedings Library Archive / Volume 482 / 1997
- Published online by Cambridge University Press:
- 10 February 2011, 185
- Print publication:
- 1997
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The epitaxy, defect structure, and heterointerface microstructure of MOVPE-grown AlN on <111> oriented Si were studied by transmission electron microscopy (TEM) in an investigation of the affects of the growth temperature (925°C–1 175°C) on the microstructure of low thickness (∼0.2 μm) films. A film grown at 1175°C was single crystalline with the following orientation relationship: (0001)AlN||(111)Si, <1120> and <1010>AlN||<211> Si. All AlN films grown at temperatures below 1100°C were wire-textured polycrystals with (0001)AlN largely parallel to (111)si and some in-plane preferred orientation similar to that of 1175°C AlN epifilms. Columnar grains/domains with faceted top surfaces were observed for the entire growth temperature range. The mean column diameters decreased from 50 nm to 35 nm as the growth temperature decreased. The columnar grain/domain structure and the faceted tops resulted in peakto-valley surface roughness on the order of 20 nm. Sharp interfaces of AlN/Si were generally observed in all AIN films studied by HREM except for the 1075°C film where a transitional layer of approximately 15Å thick was observed at some interface regions. Defects typically encountered in large lattice mismatched heteroepitaxial systems were observed.
Variation of GaN Valence Bands with Biaxial Stress: Quantification of Residual Stress and Impact on Fundamental Band Parameters
- N. V. Edwards, S. D. Yoo, M. D. Bremser, M. N. Horton, N. R. Perkins, T. W. Weeks, Jr., H. Liu, R. A. Stall, T. F. Kuech, R. F. Davis, D. E. Aspnes
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- Journal:
- MRS Online Proceedings Library Archive / Volume 449 / 1996
- Published online by Cambridge University Press:
- 10 February 2011, 781
- Print publication:
- 1996
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We provide the widest estimate thus far of the range of tensile and compressive stress (−3.8 to 3.5 kbar) that GaN epitaxial material can withstand before relaxation occurs, and an unambiguous determination of the spin-orbit splitting Δso = 17.0 ± 1 meV for the material. These are achieved by analyzing 10K reflectance data for the energy separation of transitions between the uppermost valence bands and the lowest conduction band of wurtzitic GaN as a function of biaxial stress for a series of GaN films grown on both Al2O3 and 6H-SiC substrates. Our data explicitly show the nonlinear behavior of the excitonic energy splittings B-A and C-A vs. the energy position of the A exciton, which stands in contrast to the linear approximations used by previous workers analyzing material grown only on Al2O3 substrates. Further, the lineshape ambiguities present in GaN reflectance spectra that hindered the accurate determination of such excitonic energies have also been resolved by analyzing these data in reciprocal space, where critical point energies are determined by phase effects to an accuracy of ±0.5 meV.
An open letter to the President
- Louis Appleby, Glyn Lewis, R. H. Cawley, Isaac Marks, Pamela Taylor, Raymond Levy, Klaus Bergmann, Nick Temple, Brian Toone, Stephen Wolkind, Eileen Joyce, Michael Gill, E. Guinness, Michael Farrell, V. L. Nimgaonkar, Deborah Chee, L. Mynors-Wallis, Peter Jones, Penny Thompson, Rachel Brown, H. Ring, Claire Gerada, Jenny Bearn, S. G. Potts, B. C. Beats, Lyn Pilowsky, Judith Jackson, G. F. Searle, Keith Lloyd, Helena Fox, Parimela Moodley, Tony Maden, S. W. Lewis, M. W. Orrell, D. Murphy, W. J. Levy, Brian Green, Alex Buchanan, Marian J. Perkins, Peter Misch, Gillian Mezey, M. Murphy, Anthony David, Robert Kerwin, Shirine Pezeshgi, M. Abas, P. Silverstone, J. H. Stone, G. O. 'Sullivan, R. Araya, R. Ball, E. Palazidou, Jane Milton, Anthony J. Pelosi, Janet Carrick, Dinesh Bhugra, Chris Hollis, Mark Berelowitz, N. R. Fisher, Deborah Brooke, Charles Hindler, Malcolm Battersby, Abigail Seltzer
-
- Journal:
- Psychiatric Bulletin / Volume 12 / Issue 12 / December 1988
- Published online by Cambridge University Press:
- 02 January 2018, p. 554
- Print publication:
- December 1988
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Foreign Relations of the United States, 1949, Vol. VI, The Near East, South Asia, and Africa. Washington: U.S. Govt. Printing Office, 1977. Pp. xi, 1852. Index. $16.50.
- E. R. Perkins
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- American Journal of International Law / Volume 72 / Issue 4 / October 1978
- Published online by Cambridge University Press:
- 27 February 2017, pp. 954-956
- Print publication:
- October 1978
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