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Associations between antibiotic prescriptions and recurrent urinary tract infections in female college students
- S. N. Rich, E. M. Klann, C. R. Almond, E. M. Larkin, G. Nicolette, J. D. Ball
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- Journal:
- Epidemiology & Infection / Volume 147 / 2019
- Published online by Cambridge University Press:
- 08 March 2019, e119
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Urinary tract infections (UTIs) are common among college-aged women and often recur. Some antibiotics recommended to treat UTIs trigger dysbiosis of intestinal and vaginal microbiomes – where uropathogens originate, though few studies have investigated associations between these therapies with recurrent infections. We retrospectively analysed the electronic medical records of 6651 college-aged women diagnosed with a UTI at a US university student health centre between 2006 and 2014. Women were followed for 6 months for incidence of a recurrent infection. In a secondary analysis, associations in women whose experienced UTI recurrence within 2 weeks were also considered for potential infection relapse. Logistic regression was used to assess associations between infection recurrence or relapse and antibiotics prescribed, in addition to baseline patient characteristics including age, race/ethnicity, region of origin, year of encounter, presence of symptomology, pyelonephritis, vaginal coinfection and birth control consultation. There were 1051 instances of infection recurrence among the 6620 patients, indicating a prevalence of 16%. In the analysis of patient characteristics, Asian women were statistically more likely to experience infection recurrence whereas African American were less likely. No significant associations were identified between the antibiotic administered at the initial infection and the risk of infection recurrence after multivariable adjustment. Treatment with trimethoprim-sulphamethoxazole and being born outside of the USA were significantly associated with increased odds of infection relapse in the multivariate analysis. The results of the analyses suggest that treatment with trimethoprim-sulphamethoxazole may lead to an increased risk of UTI relapse, warranting further study.
NEW TAXA AND NEW COMBINATIONS IN THE BRITISH FLORA
- T. C. G. Rich, A. McVeigh, C. A. Stace
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- Journal:
- Edinburgh Journal of Botany / Volume 76 / Issue 2 / July 2019
- Published online by Cambridge University Press:
- 03 December 2018, pp. 173-180
- Print publication:
- July 2019
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Four new taxa and nine new combinations are required for forthcoming floristic works by the authors. The new taxa are Centaurium tenuiflorum (Hoffmanns. & Link) Fritsch subsp. anglicum T.C.G.Rich & McVeigh, subsp. nov.; Centaurium × klattii P.Fourn. ex T.C.G.Rich, hyb. nov.; Centaurium × ubsdellii T.C.G.Rich, hyb. nov.; and Gentianella amarella (L.) Börner subsp. occidentalis T.C.G.Rich & McVeigh, subsp. nov. The new combinations are Centaurium erythraea Rafn var. latifolium (Sm.) T.C.G.Rich, comb. et stat. nov.; Gentianella amarella (L.) Börner subsp. anglica (Pugsley) T.C.G.Rich & McVeigh, comb. et stat. nov.; Aria parviloba (T.C.G.Rich) Sennikov & Kurtto, comb. nov.; Cotula sessilis (Ruiz & Pav.) Stace, comb. nov.; Elymus × drucei (Stace) Stace, comb. nov.; Elymus repens (L.) Gould f. aristatus (Schumach.) Stace, comb. nov.; Elymus athericus (Link) Kerguélen f. setigerus (Dumort.) Stace, comb. nov.; Ulmus minor Mill. subsp. cornubiensis (Weston) Stace, comb. et stat. nov.; and Dysphania ambrosioides (L.) Mosyakin & Clemants var. anthelmintica (L.) Stace, comb. nov.
Meta-analysis across Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium provides evidence for an association of serum vitamin D with pulmonary function
- Jiayi Xu, Traci M. Bartz, Geetha Chittoor, Gudny Eiriksdottir, Ani W. Manichaikul, Fangui Sun, Natalie Terzikhan, Xia Zhou, Sarah L. Booth, Guy G. Brusselle, Ian H. de Boer, Myriam Fornage, Alexis C. Frazier-Wood, Mariaelisa Graff, Vilmundur Gudnason, Tamara B. Harris, Albert Hofman, Ruixue Hou, Denise K. Houston, David R. Jacobs, Jr, Stephen B. Kritchevsky, Jeanne Latourelle, Rozenn N. Lemaitre, Pamela L. Lutsey, George O’Connor, Elizabeth C. Oelsner, James S. Pankow, Bruce M. Psaty, Rebecca R. Rohde, Stephen S. Rich, Jerome I. Rotter, Lewis J. Smith, Bruno H. Stricker, V. Saroja Voruganti, Thomas J. Wang, M. Carola Zillikens, R. Graham Barr, Josée Dupuis, Sina A. Gharib, Lies Lahousse, Stephanie J. London, Kari E. North, Albert V. Smith, Lyn M. Steffen, Dana B. Hancock, Patricia A. Cassano
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- Journal:
- British Journal of Nutrition / Volume 120 / Issue 10 / 28 November 2018
- Published online by Cambridge University Press:
- 12 September 2018, pp. 1159-1170
- Print publication:
- 28 November 2018
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The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Barriers to Providing Prehospital Care to Ischemic Stroke Patients: Predictors and Impact on Care
- Timmy Li, Jeremy T. Cushman, Manish N. Shah, Adam G. Kelly, David Q. Rich, Courtney M. C. Jones
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- Journal:
- Prehospital and Disaster Medicine / Volume 33 / Issue 5 / October 2018
- Published online by Cambridge University Press:
- 29 August 2018, pp. 501-507
- Print publication:
- October 2018
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Introduction
Ischemic stroke treatment is time-sensitive, and barriers to providing prehospital care encountered by Emergency Medical Services (EMS) providers have been under-studied.
Hypothesis/ProblemThis study described barriers to providing prehospital care, identified predictors of these barriers, and assessed the impact of these barriers on EMS on-scene time and administration of tissue plasminogen activator (tPA) in the emergency department (ED).
MethodsA retrospective cohort study was performed using the Get With The Guidelines-Stroke (GWTG-S; American Heart Association [AHA]; Dallas, Texas USA) registry at two hospitals to identify ischemic stroke patients arriving by EMS. Variables were abstracted from prehospital and hospital medical records and merged with registry data. Barriers to care were grouped into themes. Logistic regression was used to identify predictors of barriers to care, and bi-variate tests were used to assess differences in EMS on-scene time and the proportion of patients receiving tPA between patients with and without barriers.
ResultsBarriers to providing prehospital care were documented for 15.5% of patients: 29.6% related to access, 26.7% communication, 23.0% extrication and transportation, 20.0% refusal, and 14.1% assessment/management. Non-white and non-black race (OR: 3.69; 95% CI, 1.63-8.36) and living alone (OR: 1.53; 95% CI, 1.05-2.23) were associated with greater odds of barriers to providing care. The EMS on-scene time was ≥15 minutes for 70.4% of patients who had a barrier to care, compared with 49.0% of patients who did not (P<.001). There was no significant difference in the proportion of patients who were administered tPA between those with and without barriers to care (14.1% vs 19.2%; P=.159).
ConclusionsBarriers to providing prehospital care were documented for a sizable proportion of ischemic stroke patients, with the majority related to patient access and communication, and occurred more frequently among non-white and non-black patients and those living alone. Although EMS on-scene time was longer for patients with barriers to care, the proportion of patients receiving tPA in the ED did not differ.
,Li T ,Cushman JT ,Shah MN ,Kelly AG ,Rich DQ .Jones CMC Barriers to Providing Prehospital Care to Ischemic Stroke Patients: Predictors and Impact on Care . Prehosp Disaster Med.2018 ;33 (5 ):501 –507 .
P033: Reducing pantoprazole infusions in ED GI bleed patients by optimizing electronic order sets
- S. K. Dowling, E. S. Lang, G. Kaplan, K. Novak, C. Hall, J. King, J. Larsson, T. Rich
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- Journal:
- Canadian Journal of Emergency Medicine / Volume 20 / Issue S1 / May 2018
- Published online by Cambridge University Press:
- 11 May 2018, p. S68
- Print publication:
- May 2018
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Introduction: Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common presentation to the emergency department (ED) accounting for significant morbidity, mortality and health care resource usage. In Alberta, a provincial care pathway was recently developed to provide an evidence informed approach to managing patients with an UGIBs in the ED. Pantoprazole infusions are a commonly used treatment despite evidence that suggests they are generally not indicated prior to endoscopy in the ED. The goal of this project was to optimize management of patients with a NVUGIB, in particular reduce pre-endoscopy pantoprazole infusions. Methods: In July 2016, we implemented a multi-faceted intervention to optimize management of ED patients with NVUGIB including 1. de-emphasizing IV pantoprazole infusions in the ED, 2. clinical decision support (CDS) embedded (for endoscopy, disposition and transfusions) within the order set and 3. educating clinicians about the care pathway. We used a pre/post-order set design, analyzing 391 days pre and 189 days post-order set changes. Data was extracted from our fully integrated electronic health records system. The primary outcome was the % of patients receiving IV pantoprazole infusion ordered by an emergency physician (EP) among all patients with NVUGIB. Secondary outcomes included % transfused with hgb >70g/L and whether using the GIB order set impacted management of NVUGIB patients. Results: In the 391 days pre-order set changes, there were 2165 patients included and in the 189 days post-order set changes, there were 901 patients. For baseline characteristics, patients in the post-order set change group were significantly older (64.4 yrs vs 60.9 yrs p-value=0.0016) and had a lower hgb (115 vs 118, p-value=0.049) but otherwise for gender, measures of severity of illness (systolic blood pressure, heart rate, CTAS, % admitted) there were no significantly differences. For the primary outcome, in the pre-order set phase, 47.1% received a pantoprazole infusion ordered by an EP, compared to 31.5% in the post-order phase, for an absolute reduction of 15.6% (p-value= <0.001). For the secondary outcomes, transfusion rates were similar pre/post (22.08% vs 22.75%). Significant inter-site variability exists with respect to the reduction in pantoprazole infusion rates across the four sites (-23.3% to +6.12%). Conclusion: Our interventions resulted in a significant overall reduction in pantoprazole infusions in ED patients with NVUGIB. Reductions in pantoprazole infusions varied significantly across the different sites, future work in our department will explore and address this variability. Keys to the success of this project included engaging clinicians as well as leveraging the SCM order sets as well as the provincial care pathway. Although there were no changes in transfusion rates, it in unclear if this a function of the CDS not being effective or whether these transfusions were clinically indicated.
Towards meeting VLTA challenges for evacuation slides and slide-rafts
- P. D. Gosling, C. G. Riches
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- Journal:
- The Aeronautical Journal / Volume 107 / Issue 1070 / April 2003
- Published online by Cambridge University Press:
- 04 July 2016, pp. 185-200
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The intrinsic dependence on the necessary minimum structural performance of inflatable aircraft evacuation slides and slide-rafts in the event of and emergency or precautionary aircraft evacuation is described in the context of the certification of both new (or modified) aircraft and slide designs. The concepts of the pneumatic structure with analytical and numerical methodologies are briefly reviewed. Fundamental principles of inflatable evacuation slide performance and assessment are presented, while the characteristics of typical structural responses are identified for single deck aircraft. The implications of evacuation from an upper deck of a VLTA are identified in the interpretation of two new commercial inflatable evacuation slide designs. Alternative meso and macro pneumatic structural forms are proposed as evolutions of the conventional inflated tube. Outline details of a simple mixed finite element and vector-based simulation algorithm for the analysis of pneumatic structures precede examples verifying the numerical formulation and demonstrating the potential of multi-cell beam (meso) and “semi-pneumatic shell membrane” (macro) pneumatic concepts. Recommendations for future research conclude the paper.
Contributors
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- By Janice Capel Anderson, S. Wesley Ariarajah, Constantine Belezos, Ian Boxall, Marc Zvi Brettler, Edward Breuer, Daniel Bruno, Mark Chapman, W. T. Dickens, Mark W. Elliott, Eldon Epp, Tassilo Erhardt, Timothy Gorringe, Harriet Harris, Peter C. Hodgson, Leslie Howsam, Werner G. Jeanrond, Scott McLaren, Wayne A. Meeks, Néstor Míguez, Stephen D. Moore, Robert Morgan, Halvor Moxnes, Peter Neuner, Mark Noll, Jorunn Økland, Gaye Ortiz, John Riches, Christopher Rowland, Nicolaas A. Rupke, Edmund J. Rybarczyk, Lamin Sanneh, Constantine Scouteris, R. S. Sugirtharajah, Willard M. Swartley, William R. Telford, David Thompson, Elena Volkova, J. R. Watson, Gerald West, Michael Wheeler, Keith Whitelam
- Edited by John Riches, University of Glasgow
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- The New Cambridge History of the Bible
- Published online:
- 09 June 2015
- Print publication:
- 13 April 2015, pp xi-xii
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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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Ticks (Ixodoidea) of domestic animals in Cyprus
- P. D. Le Riche, Y. Altan, J. B. Campbell, G. C. Efstathiou
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- Bulletin of Entomological Research / Volume 64 / Issue 1 / August 1974
- Published online by Cambridge University Press:
- 10 July 2009, pp. 53-63
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A total of 15 835 ticks was identified, mainly from sheep and goats, in a livestock survey in Cyprus in 1970–72. Hyalomma anatolicum anatolicum Koch, H. a. excavatum Koch, H. marginatum marginatum Koch, H. m. turanicum Pom., H. m. rufipes Koch, Haemaphysalis sulcata C. & F., Ixodes crenulatus Koch and Rhipicephalus turanicus Pom. & Matikashvili are recorded for the first time in Cyprus. H. sulcata was found in all parts of the island; Hyalomma spp. and Rhipicephalus spp. were mostly seen in the low drier areas, and Ixodes gibbosus Nutt. in the wetter areas; Boophilus annulatus (Say) was confined to one small area. Ticks were most common in autumn and early winter. Haemaphysalis sulcata and I. gibbosus were only found in the winter months, whereas Hyalomma spp. were found all the year round but especially in the warmer months. The Hyalomma subspecies showed some differences in seasonal distribution. Immature Rhipicephalus ticks were found in the colder months whereas the adults were seen mainly in the spring and early summer. Immature Haemaphysalis sulcata and Hyalomma spp. were extremely rare on ruminants. Only adults of I. gibbosus were seen in the first year of the survey, whereas only immatures, mainly larvae, were seen in the second year. The period of attachment of R. bursa C. & F. adults was shorter than that of R. turanicus and corresponded closely to the incidence of babesiosis in sheep and goats. The predilection sites of ticks for cattle, sheep and goats are given.
A Helminth Survey of Sheep and Goats in Cyprus.Part I. The Seasonal Distribution and Prevalence of Gastro-Intestinal Parasites
- P. D. Le Riche, G. C. Efstathiou, J. B. Campbell, Y. Altan
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- Journal:
- Journal of Helminthology / Volume 47 / Issue 3 / September 1973
- Published online by Cambridge University Press:
- 05 June 2009, pp. 237-250
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889 complete alimentary tracts were examined for helminths during a two-year survey of sheep and goats in Cyprus. Faecal samples were also examined for worm eggs.
The most common parasites found were Ostertagia and Trichostrongylus spp. and a list of all the parasites and their prevalence is given.
Bunostomum trigonoceplialum, Parabronema skrjabini and Skrjabinema ovis were found for the first time in Cyprus.
The infection rate of each of the worms was studied and the results showed that most of the worms followed the same general pattern, having a peak in the spring and another in the autumn, separated by a trough during the hot dry summer period, when the infection rate yvas low. There were variations within this pattern, Trichostrongylus spp. having a spring peak that was more pronounced than the autumn peak. The reverse occurred with Ostertagia, Chabertia and Oesophagostomum spp., which had a more pronounced autumn peak than spring peak and a lower rate of infection in the summer.
Variations in the infection rate were also noted between the two years of study.
The reasons for these variations are discussed and it appears that weather has some influence on the timing and duration of the peaks but that other factors must also be involved. It is suggested that with some species inhibition of development of the immature stages may occur over the hot dry period, and that these immature worms resume their development towards the end of summer.
A similarity was noticed between the seasonal distribution of the different worm species in Cyprus and in the winter rainfall areas of Australia.
A Helminth Survey of Sheep and Goats in Cyprus. Part II. Age Distribution and the Severity of Infection with Gastro-Intestinal Parasites
- P. D. Le Riche, G. C. Efstathiou, Y. Altan, J. B. Campbell
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- Journal of Helminthology / Volume 47 / Issue 3 / September 1973
- Published online by Cambridge University Press:
- 05 June 2009, pp. 251-262
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889 alimentary tracts from sheep and goats were examined for worms during 1970 and 1971.
The severity of infection with each of the worm species is discussed and it is concluded that infections with Ostertagia spp. and Trichostrongylus spp. are the most important and that Haemonchus contortus, Bunostomum trigonocephalum and Chabertia ovina are of secondary importance.
The animals were divided into different age groups and a study was made of the severity of mixed infections in each group. The point system adopted by Parnell et al. (1954) was used for the study.
The most unexpected finding was that lambs and kids under 8 months old rarely suffered from infections of any significance. Infections built up slowly after that age. It was therefore presumed that animals remained vulnerable to infections at a much later age than in other countries.
Infections that might cause sub-clinical disease were seen in 31% of all animals and heavier infections were seen in 20% of the animals. This was considered a conservative estimate and shows the importance of gastro-intestinal parasites in sheep and goats in Cyprus.
Adult sheep appeared to be more heavily infected than goats, although some differences in animal husbandry between the two may have contributed to this.
From this study of age distribution, it was found that the autumn peak in the infection rate was not caused by the infection of young animals, which remained low at this time of the year.
Insights About Induced SFR in the Shell Systems of Early-Type Galaxies from UV (GALEX)
- L. M. Buson, D. Bettoni, A. Marino, C. Chiosi, G. Galletta, R. Rampazzo, R. Tantalo, R. M. Rich
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- Journal:
- Proceedings of the International Astronomical Union / Volume 2 / Issue S235 / August 2006
- Published online by Cambridge University Press:
- 01 August 2006, p. 305
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- August 2006
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We present UV data of a small sample of shell galaxies. For the majority of them (namely, NGC 2865 and NGC 7135), the NUV matches the optical emission, while the FUV is present in the innermost regions alone.
Getting closer to suicide prevention
- G. Isacsson, C. L. Rich
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- Journal:
- The British Journal of Psychiatry / Volume 182 / Issue 5 / May 2003
- Published online by Cambridge University Press:
- 02 January 2018, p. 457
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- May 2003
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DISTRIBUTION MAPS AND IUCN THREAT CATEGORIES FOR HIERACIUM SECTION ALPINA (ASTERACEAE ) IN BRITAIN
- D. J. TENNANT, T. C. G. RICH
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- Journal:
- Edinburgh Journal of Botany / Volume 59 / Issue 3 / November 2002
- Published online by Cambridge University Press:
- 14 November 2002, pp. 351-372
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- November 2002
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Distribution maps and IUCN threat categories for the 30 named species of Hieracium section Alpina (Asteraceae) in Britain are given, based on taxonomic and distribution studies by D.J. Tennant and others over the last 30 years. Twenty-seven taxa are endemic to Scotland, one to England, one to Britain and one also occurs in mainland Europe and the Arctic. There are three main centres of diversity in Scotland: the Eastern Highlands (especially the Cairngorm Mountains), the Western Highlands and the Northern Highlands. Under the IUCN threat categories, seven taxa are Critically Endangered, seven are Endangered, two are Vulnerable, ten are Near Threatened and seven are Nationally Scarce. The main threats are collecting, natural events such as rock falls and avalanches, global warming, acid rain, over-grazing and tourism. There is particular concern for the long-term survival of four taxa.
TAXONOMY AND DISTRIBUTION OF EUROPEAN DAMASONIUM (ALISMATACEAE)
- T. C. G. RICH, F. L. NICHOLLS-VUILLE
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- Journal:
- Edinburgh Journal of Botany / Volume 58 / Issue 1 / March 2001
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- 26 February 2001, pp. 45-55
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- March 2001
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A review of the taxonomy and distribution of the European species of Damasonium Mill. has been carried out to provide background information for conservation. Damasonium alisma Mill., D. bourgaei Coss. and D. polyspermum Coss. are recognized as distinct species, and descriptions and a key are presented. Lectotypes are designated for D. bourgaei and D. polyspermum. Damasonium alisma is the most northerly taxon, predominantly occurring in France and England, but extending eastwards to Russia. Damasonium bourgaei is widespread around the Mediterranean eastwards at least to India. Damasonium polyspermum occurs mainly in the western Mediterranean.
Conservation of Britain's biodiversity IV: Filago pyramidata(Asteraceae), broad-leaved cudweed
- T. C. G. Rich
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- Journal:
- Edinburgh Journal of Botany / Volume 56 / Issue 1 / March 1999
- Published online by Cambridge University Press:
- 26 April 2010, pp. 61-73
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- March 1999
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This paper summarizes conservation work carried out on Filago pyramidata L. (Asteraceae), broad-leaved cudweed, between 1993 and 1996 in Britain. It was formerly native in 125 10km squares in about 240 localities. In 1993–1996 it was recorded in eight 10km squares (94% decline) in eight localities (97% decline). Historically its main habitats were arable fields, road and track sides, and heaths, commons and quarries. It has declined in arable field habitats owing to changes in agricultural practices, and from tracks and roadsides because of reduced disturbance. The decline occurred gradually before the 1970s. Populations show marked variations from year to year and marked differences between sites, owing to climate and management. The best conservation management based on practical experience is annual digging or rotavation in early autumn. The plant is under severe threat in Britain; four sites are designated as SSSIs, but two of the four largest populations are unprotected.
The Risk of Peripheral Vein Phlebitis Associated With Chlorhexidine-Coated Catheters A Randomized, Double-Blind Trial
- Robert J. Sherertz, Jeffrey L. Stephens, Randy D. Marosok, William A. Carruth, H. Anne Rich, Kenneth D. Hampton, Sandy M. Motsinger, Lynnette C. Harris, Philip E. Scuderi, James G. Pappas, Steven C. Felton, Donald D. Solomon
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 18 / Issue 4 / April 1997
- Published online by Cambridge University Press:
- 02 January 2015, pp. 230-236
- Print publication:
- April 1997
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Objective:
To evaluate the risk of phlebitis associated with chlorhexidine-coated polyurethane catheters in peripheral veins.
Design:A randomized, double-blinded trial comparing chlorhexidine-coated polyurethane catheters with uncoated polyurethane catheters.
Setting:A university hospital.
Patients:Adult medicine and surgery patients.
Interventions:Certified registered nurse anesthetists or an infusion team consisting of nurses and physicians inserted the catheters. Catheter insertion sites were scored twice daily for evidence of phlebitis. At the time catheters were removed, a quantitative blood culture was performed, and catheters were sonicated for quantitative culture.
Results:Of 221 evaluable catheters, phlebitis developed in 18 (17%) of 105 coated catheters, compared to 27 (23%) of 116 uncoated catheters (relative risk [RR], 0.74; 95% confidence interval [CI95], 0.43-1.26; P=.32). By survival analysis, chlorhexidine-coated catheters had a lower risk of phlebitis during the first 3 days (P=.06), but not when all catheters were considered in both patient groups (P=.31). In the absence of catheter colonization, the incidence of phlebitis was 21% (16/76) and 24% (20/86) for coated and uncoated catheters, respectively (P=.85), whereas in the presence of catheter colonization, the incidence of phlebitis was 14% (1/7) and 80% (4/5) for coated and uncoated catheters, respectively (RR, 0.18; CI95, 0.03-1.15; P=.07).
Conclusion:The risk of phlebitis in the presence of catheter colonization was 82% lower for chlorhexidinecoated polyurethane catheters compared to otherwise identical uncoated catheters.
The GALLEX Project
- T. Kirsten, M. Breitenbach, W. Hampel, G. Heusser, J. Kiko, T. Kirsten, H. Lalla, A. Lenzing, E. Pernicka, R. Plaga, B. Povh, C. Schlosser, H. Völk, R. Wink, K. Zuber, R.v. Ammon, K. Ebert, E. Henrich, L. Stieglitz, E. Bellotti, O. Cremonesi, E. Fiorini, C. Liguori, S. Ragazzi, L. Zanotti, R. Mössbauer, A. Urban, G. Berthomieu, E. Schatzman, S. d’Angelo, C. Bacci, P. Belli, R. Bernabei, L. Paoluzi, R. Santonico, M. Cribier, G. Dupont, B. Pichard, J. Rich, M. Spiro, T. Stolarczyk, C. Tao, D. Vignaud, I. Dostrovsky, G. Friedlander, R.L. Hahn, J.K. Rowley, R.W. Stoenner, J. Weneser
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- Journal:
- International Astronomical Union Colloquium / Volume 121 / 1990
- Published online by Cambridge University Press:
- 12 April 2016, pp. 187-199
- Print publication:
- 1990
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The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before [1-7]. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of development allows to start the first full scale run at the time when 30 tons of Gallium become available. This date is expected to be January, 1990.
Suicide in Young Doctors
- J. C. Richings, G. S. Khara, M. McDowell
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- Journal:
- The British Journal of Psychiatry / Volume 149 / Issue 4 / October 1986
- Published online by Cambridge University Press:
- 29 January 2018, pp. 475-478
- Print publication:
- October 1986
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Fifty-five cases of suicide by doctors under the age of 40 were studied because of concern about deaths among anaesthetists in training. The excess mortality of doctors from suicide was confirmed, suggesting that risk factors associated with being a member of the medical profession continue to operate, although mortality for young male doctors from accidental poisoning is falling. Analysis of the branches of medicine in which the doctors were working showed no definite specialty predominance. There was a somewhat greater risk for women doctors born overseas.
Negative Charge of Dioctahedral Micas as Related to Weathering
- M. G. Cook, C. I. Rich
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- Journal:
- Clays and clay minerals (National Conference on Clays and Clay Minerals) / Volume 11 / February 1962
- Published online by Cambridge University Press:
- 01 January 2024, pp. 47-64
- Print publication:
- February 1962
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Negative charge and related characteristics of dioctahedral micas have been investigated by conducting artificial weathering studies on a muscovite from Ontario, Canada, and saprolitic micas from Virginia. Emphasis is given to the relationship between loss of potassium, increase in net negative charge, or cation exchange capacity, and expansion characteristics.
Boiling solutions of acetic acid, sodium chloride and magnesium chloride removed potassium and sodium from a saprolitic mica but produced a negligible increase in cation exchange capacity. Expansion of the mica structure occurred following treatment with salt solutions but not with acid solutions. Boiling solutions of sodium citrate removed potassium effectively, produced marked expansion, and caused a large increase in cation exchange capacity. The small increase in cation exchange capacity resulting from acid and salt treatments is attributed to the hydrolysis of exchangeable aluminum to form hydroxy-aluminum polymeric groups, which can occupy exchange sites but remain non-exchangeable. The results of the sodium citrate tratement are attributed to the complexing of aluminum by citrate, thus releasing the hydroxy-aluminum polymeric groups from exchange positions and permitting an increase in cation exchange capacity.
Molten lithium nitrate treatment of specimen muscovite produced a greater increase in cation exchange capacity than in the case of muscovite separated from soil-forming mica phyllite. The observed difference in charge characteristics, concomitant with the greater expansion of the muscovite, suggest that soil micas and specimen-type micas differ in their alteration tendencies.
When interlayer hydroxy groups are eliminated and account is taken of residual sodium, potassium, and water, dioctahedral micas apparently lose no negative charge on expansion to vermiculite-like minerals.