18 results
Uncovering key clinical trial features influencing recruitment
- Betina Idnay, Yilu Fang, Alex Butler, Joyce Moran, Ziran Li, Junghwan Lee, Casey Ta, Cong Liu, Chi Yuan, Huanyao Chen, Edward Stanley, George Hripcsak, Elaine Larson, Karen Marder, Wendy Chung, Brenda Ruotolo, Chunhua Weng
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- Journal:
- Journal of Clinical and Translational Science / Volume 7 / Issue 1 / 2023
- Published online by Cambridge University Press:
- 04 September 2023, e199
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Background:
Randomized clinical trials (RCT) are the foundation for medical advances, but participant recruitment remains a persistent barrier to their success. This retrospective data analysis aims to (1) identify clinical trial features associated with successful participant recruitment measured by accrual percentage and (2) compare the characteristics of the RCTs by assessing the most and least successful recruitment, which are indicated by varying thresholds of accrual percentage such as ≥ 90% vs ≤ 10%, ≥ 80% vs ≤ 20%, and ≥ 70% vs ≤ 30%.
Methods:Data from the internal research registry at Columbia University Irving Medical Center and Aggregated Analysis of ClinicalTrials.gov were collected for 393 randomized interventional treatment studies closed to further enrollment. We compared two regularized linear regression and six tree-based machine learning models for accrual percentage (i.e., reported accrual to date divided by the target accrual) prediction. The outperforming model and Tree SHapley Additive exPlanations were used for feature importance analysis for participant recruitment. The identified features were compared between the two subgroups.
Results:CatBoost regressor outperformed the others. Key features positively associated with recruitment success, as measured by accrual percentage, include government funding and compensation. Meanwhile, cancer research and non-conventional recruitment methods (e.g., websites) are negatively associated with recruitment success. Statistically significant subgroup differences (corrected p-value < .05) were found in 15 of the top 30 most important features.
Conclusion:This multi-source retrospective study highlighted key features influencing RCT participant recruitment, offering actionable steps for improvement, including flexible recruitment infrastructure and appropriate participant compensation.
15 - Being a member of an interprofessional team
- from Part 3 - Being
- Edited by Nick Arnott, University of Tasmania, Penny Paliadelis, Mary Cruickshank
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- Book:
- The Road to Nursing
- Published online:
- 28 February 2022
- Print publication:
- 22 November 2021, pp 292-307
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Summary
Communication is recognised as an important factor in interprofessional collaboration and teamwork. The delivery of optimal person-centred care ‘requires healthcare professionals to effectively communicate, cooperate and collaborate with each other’ (Stanley & Stanley 2019). Interprofessional communication can ensure that information is shared with a collective purpose and clearly defined goals. Thomson and colleageues(2015) demonstrated that having a shared purpose to pursue quality improvement as well as collaboration provides a framework for interprofessional, person-centred care that is highly dependent on effective communication. This chapter outlines the principles of interprofessional communication as well as five competencies that can contribute to collaborative practice. Handover frameworks are explored, along with the value of teamwork. The chapter also examines how nurses and other health professionals recognise and understand conflict as it discusses strategies for managing difficult situations. Finally, professional development is explored through peer learning, mentoring and supervision, with some examples of how this can be achieved.
6 Presence and Impact of Possible Tardive Dyskinesia in Patients Prescribed Antipsychotics: Results from the RE-KINECT Study
- Andrew J. Cutler, Stanley N. Caroff, Caroline M. Tanner, Huda Shalhoub, William R. Lenderking, Jun Chen, Karen Yeomans, Ericha Anthony, Chuck Yonan
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- Journal:
- CNS Spectrums / Volume 24 / Issue 1 / February 2019
- Published online by Cambridge University Press:
- 12 March 2019, pp. 176-177
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Objective
Tardive dyskinesia (TD) is a hyperkinetic movement disorder associated with antipsychotic treatment. RE KINECT (NCT03062033), a real-world study of outpatients prescribed antipsychotics, was designed to identify the presence of possible TD and characterize the impact of involuntary movements on functioning and quality of life. Data from RE-KINECT were used to compare the impact of possible TD in patients with schizophrenia/schizoaffective disorder [SZD] versus mood/other psychiatric disorders [Mood].
MethodsAdults with ≥3months of lifetime exposure to antipsychotics and ≥1 psychiatric disorder were recruited. The presence of possible TD was based on clinicians’ observation of involuntary movements in 4 body regions (head, trunk, upper extremities, and lower extremities). Baseline outcomes included demographics, medication history, location/severity of abnormal movements, impact of abnormal movements on daily activities, the Sheehan Disability Scale (SDS), and the EuroQoL 5-Dimensional questionnaire (EQ-5D-5L).
ResultsOf 204 patients with clinician-confirmed possible TD, 111 (54.4%) had a SZD diagnosis and 93 (45.6%) had a mood/other psychiatric diagnosis. Significant differences found between groups (Mood vs SZD) included: mean age (56.9 vs 52.7 years; P=0.0263); male sex (33.3% vs 62.2%; P<0.0001); African-American race (7.5% vs 26.1%; P=0.0005); mean lifetime exposure to antipsychotics (9.5 vs 19.5 years; P<0.0001); and percentage of patients currently taking ≥2 psychiatric medications (93.5% vs 79.3%; P=0.0093). Based on clinician observation, there were no significant differences between diagnosis groups in the number of body regions impacted by abnormal movements, maximum severity score across all 4 regions, or patient awareness of possible TD. Over 30% of patients in both groups reported that involuntary movements had “some” or “a lot” of impact on their ability to continue usual activities, be productive, and socialize. No significant differences between the diagnosis groups (Mood vs SZD) were found for mean SDS total score (12.8 vs 10.8), SDS domain scores (work/school [4.1 vs 4.2], social life [4.3 vs 3.7], family life [4.1 vs 3.5]), EQ-5D-5L utility score (0.68 vs 0.74), or EQ-5D-5L health state VAS (64.8 vs 68.5).
ConclusionsIn this cohort of outpatients with possible TD, those with Mood disorders were more likely to be older, female, and white than patients with SZD. The ability to function and quality of life were equally impaired in both groups. Further studies on the impact of TD are needed.
Funding Acknowledgements: Neurocrine Biosciences, Inc.
117 RE-KINECT: Real-World Dyskinesia Screening Study and Registry in Patients Taking Antipsychotic Agents: Interim Baseline Burden of Illness Results
- Andrew Cutler, Stanley Caroff, Caroline Tanner, William R. Lenderking, Karen Yeomans, Huda Shalhoub, Véronique Pagé, Chuck Yonan
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- Journal:
- CNS Spectrums / Volume 23 / Issue 1 / February 2018
- Published online by Cambridge University Press:
- 15 June 2018, p. 74
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Background
Tardive dyskinesia (TD) is associated with prolonged exposure to dopamine receptor blockers including antipsychotics. This registry describes the prevalence and impact of involuntary movements (possible TD) in a real-world population of patients taking antipsychotics.
MethodsRE-KINECT (NCT03062033) aims to enroll 1,000 patients from 70 US psychiatric practices. Adults with ≥3 months lifetime exposure to antipsychotic(s) and ≥1 psychiatric disorder are eligible for two-tier screening: informal observation, and then clinician observation of abnormal involuntary movements in general body regions (head/face, neck/trunk, upper/lower limbs) and confirmation of possible TD. Based on clinician assessment, patients are assigned to Cohort 1 or Cohort 2 (without or with abnormal involuntary movements, respectively). In both cohorts, the following baseline assessments are included: clinician’s assessment of clinical psychiatric severity, patient perceived health‐related quality of life (EuroQOL 5-Dimensions), social burden/disability questionnaire (Sheehan Disability Scale), and 12-month retrospective chart review ofmedical and treatment history. Cohort 2 also participate in 12-month longitudinal evaluation. Interim baseline data are available from four sites.
ResultsBaseline data are currently available for 116 patients—mean age, 49.6 years; female, 60.3%; schizophrenia/schizoaffective disorder, 32.8%; at least 1 mood disorder, 84.5%, and 10.4 years mean cumulative lifetime exposure to antipsychotic(s). The most concerning health condition for both cohorts is their mental health (69.0%), followed by physical activity and nutrition (33.6%). 32.8% of subjects had clinician confirmation of possible TD.
ConclusionThis novel registry aims to evaluate the real-world potential impact/burden of TD. Preliminary analyses suggest that TD is common in patients with schizophrenia and mood disorders taking antipsychotics. Further analyses will explore the burden of illness in this population.
Funding AcknowledgementsThis study was funded by Neurocrine Biosciences, Inc.
Four - Socialising heritage/socialising legacy
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- By Martin Bashforth, Mike Benson, Tim Boon, Lianne Brigham, Richard Brigham, Karen Brookfield, Peter Brown, Danny Callaghan, Jean-Phillipe Calvin, Richard Courtney, Kathy Cremin, Paul Furness, Helen Graham, Alex Hale, Paddy Hodgkiss, John Lawson, Rebecca Madgin, Paul Manners, David Robinson, John Stanley, Martin Swan, Jennifer Timothy, Rachael Turner
- Edited by Keri Facer, University of Bristol, Kate Pahl, Manchester Metropolitan University
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- Book:
- Valuing Interdisciplinary Collaborative Research
- Published by:
- Bristol University Press
- Published online:
- 05 April 2022
- Print publication:
- 05 April 2017, pp 85-106
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Summary
Introduction
At some point during our inaugural research team workshop we started to generate many different ideas about how to increase participation in heritage decision-making. We tried to keep track as the questions flowed by writing recurring words on pieces of paper, to be linked, connected and ordered at some later point. The words were in some ways not surprising. Heritage, of course. Stewardship. Custodianship. Expert. Leadership. Institutions. Ownership. Differences/Tensions. Scale. Personal. Values. Voice (‘+ not heard’, was added in another hand in biro). So far, so predictable. These words, after all, index the big conceptual challenges that have been identified to a greater or lesser extent in heritage policy, practice and its research for the last four decades. Yet as we spoke, each of these terms started to change in dimension. As the different people around the table gave examples, and checked they understood each other's contributions, the familiar words were in the process of gathering new uncertainties and ambiguities as well as new colours, textures, shapes and potentials.
We were brought together by a funding scheme that supported not just collaborative research, but also its collaborative design. While we did have a shared interest in our overall question ‘how should heritage decisions be made?’, we – as you will see by how we describe ourselves – came to this question, and our first workshop, from quite different places and different trajectories. To frame it in the language implied by this book, we carried with us different inheritances – legacies – from our disciplines, professional backgrounds, organisations and places. As such, the other crucial thing we had in common was an interest in the potential for rethinking ‘heritage’ offered by drawing on many different perspectives and working across hierarchies and institutional boundaries. We used both these shared commitments and our different perspectives to collaboratively design our project.
In this chapter we tell the story of our project with the aim of showing how our research emerged through dynamic connections between know-how generated through practitioner reflections, dialogue, characterised by conversations between us as a project team and conceptual innovation, in terms of the way this allowed us to think about heritage and decision making differently.
Macroevolutionary differences between the two major clades of Neogene planktonic foraminifera
- Steven M. Stanley, Karen L. Wetmore, James P. Kennett
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- Journal:
- Paleobiology / Volume 14 / Issue 3 / Summer 1988
- Published online by Cambridge University Press:
- 08 February 2016, pp. 235-249
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Being of especially high quality, the Neogene fossil record of planktonic foraminifera offers special opportunities for assessing patterns of extinction and speciation. A variety of metrics indicates that within this group the mean duration of lineages has been much shorter (rate of extinction has been higher) for the globorotaliid clade than for the globigerinid clade. Furthermore, in the globorotaliid clade rates of extinction and speciation have not been closely linked to changes in diversity, but rather have been relatively high even at times when diversity has undergone little change. Thus, the globorotaliid clade has undergone more rapid evolutionary turnover than the globigerinid clade. Data for living species reveal that neither geographic range nor temperature tolerance is the primary factor controlling lineage duration. On the other hand, there is evidence that lineages marked by low abundance (small population size) are relatively short-lived. The reason that globorotaliid lineages have generally survived for shorter intervals, on the average, may be that their populations have been less abundant and less stable. Usually they live deeper in the water column, where food is often sparse, and many flourish only in areas of upwelling. Furthermore, the globorotaliids lack symbiotic algae for nutritional support. The same ecological factors may have accelerated speciation in the globorotaliid clade, by causing species to be patchily distributed. Thus, population size and structure have been more important than geographic range in determining rates of extinction and speciation. This parallels the situation for Neogene marine bivalves.
For planktonic foraminifera, as for Western Atlantic Bivalvia, the normal pattern of extinction was reversed in late Pliocene time, apparently in response to climatic cooling. The globigerinids suffered a sudden pulse of extinction. The deeper dwelling globorotaliids fared better; probably many of their species benefited from elevation of the seasonal thermocline into the photic zone. At the same time, rate of speciation declined in the globorotaliid clade, which supports the idea, inferred from the evolutionary history of marine bivalves, that an increase in the size and stability of populations should depress both rate of extinction and rate of speciation.
Do patients with young onset Alzheimer's disease deteriorate faster than those with late onset Alzheimer's disease? A review of the literature
- Karen Stanley, Zuzana Walker
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- Journal:
- International Psychogeriatrics / Volume 26 / Issue 12 / December 2014
- Published online by Cambridge University Press:
- 03 July 2014, pp. 1945-1953
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Background:
Young onset Alzheimer's disease (YOAD; onset before 65 years of age) is thought to have a more rapid course and increased rate of progression compared to late onset Alzheimer's disease (LOAD). This assumption appears partly due to important clinical, structural, neuropathological, and neurochemical differences suggesting YOAD is a separate entity to LOAD. The aim in this review was to systematically identify and examine appropriate studies comparing rate of cognitive decline between patients with YOAD and patients with LOAD.
Methods:A computer-based literature search was initially undertaken, followed by citation tracking and search of related papers. Primary research studies specifically focused on the rate of cognitive decline between people with YOAD and LOAD were included. Studies were described, critically analyzed, presented, and discussed in the review.
Results:Four studies were included, of which three were longitudinal and one was a case-control study. Three of the included studies found a faster rate of decline in patients with YOAD, and one found no difference in rate of decline between the two groups.
Conclusions:The findings of the review are mixed and conflicting, and limited by the heterogeneity of the included studies. There is a need for future research to design systematic studies that include sufficient sample sizes and follow-up periods, and control for possible confounding factors such as education level, baseline cognitive impairment, and vascular risk factors. This will help to validate the findings so far and improve our understanding of the rate of cognitive decline in people with YOAD and LOAD.
On the set of zero coefficients of a function satisfying a linear differential equation
- JASON P. BELL, STANLEY N. BURRIS, KAREN YEATS
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- Journal:
- Mathematical Proceedings of the Cambridge Philosophical Society / Volume 153 / Issue 2 / September 2012
- Published online by Cambridge University Press:
- 22 February 2012, pp. 235-247
- Print publication:
- September 2012
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Let K be a field of characteristic zero and suppose that f:
→ K satisfies a recurrence of the form \[ f(n) = \sum_{i=1}^d P_i(n) f(n-i), \]for n sufficiently large, where P1(z),. . .,Pd(z) are polynomials in K[z]. Given that Pd(z) is a nonzero constant polynomial, we show that the set of n ∈for which f(n) = 0 is a union of finitely many arithmetic progressions and a finite set. This generalizes the Skolem–Mahler–Lech theorem, which assumes that f(n) satisfies a linear recurrence. We discuss examples and connections to the set of zero coefficients of a power series satisfying a homogeneous linear differential equation with rational function coefficients.
Neuropsychological Profile of Parkin Mutation Carriers with and without Parkinson Disease: The CORE-PD Study
- Elise Caccappolo, Roy N. Alcalay, Helen Mejia-Santana, Ming-X. Tang, Brian Rakitin, Llency Rosado, Elan D. Louis, Cynthia L. Comella, Amy Colcher, Danna Jennings, Martha A. Nance, Susan Bressman, William K. Scott, Caroline M. Tanner, Susan F. Mickel, Howard F. Andrews, Cheryl Waters, Stanley Fahn, Lucien J. Cote, Steven Frucht, Blair Ford, Michael Rezak, Kevin Novak, Joseph H. Friedman, Ronald F. Pfeiffer, Laura Marsh, Brad Hiner, Andrew D. Siderowf, Barbara M. Ross, Miguel Verbitsky, Sergey Kisselev, Ruth Ottman, Lorraine N. Clark, Karen S. Marder
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- Journal:
- Journal of the International Neuropsychological Society / Volume 17 / Issue 1 / January 2011
- Published online by Cambridge University Press:
- 24 November 2010, pp. 91-100
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The cognitive profile of early onset Parkinson’s disease (EOPD) has not been clearly defined. Mutations in the parkin gene are the most common genetic risk factor for EOPD and may offer information about the neuropsychological pattern of performance in both symptomatic and asymptomatic mutation carriers. EOPD probands and their first-degree relatives who did not have Parkinson’s disease (PD) were genotyped for mutations in the parkin gene and administered a comprehensive neuropsychological battery. Performance was compared between EOPD probands with (N = 43) and without (N = 52) parkin mutations. The same neuropsychological battery was administered to 217 first-degree relatives to assess neuropsychological function in individuals who carry parkin mutations but do not have PD. No significant differences in neuropsychological test performance were found between parkin carrier and noncarrier probands. Performance also did not differ between EOPD noncarriers and carrier subgroups (i.e., heterozygotes, compound heterozygotes/homozygotes). Similarly, no differences were found among unaffected family members across genotypes. Mean neuropsychological test performance was within normal range in all probands and relatives. Carriers of parkin mutations, whether or not they have PD, do not perform differently on neuropsychological measures as compared to noncarriers. The cognitive functioning of parkin carriers over time warrants further study. (JINS, 2011, 17, 1–10)
Contributors
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- By Louise B. Andrew, Jane C. Ballantyne, Sadek Beloucif, David Clendenin, Maliha A. Darugar, Joanna M. Davies, Michael DeVita, Denise M. Dudzinski, Bernice Elger, Monica Escher, Joel E Frader, Kelly Fryer-Edwards, James Giordano, Allen Gustin, Rebecca M. Harris, Gerhard Höver, Steven K. Howard, Carl C. Hug, Samia Hurst, Steven Jackson, Nancy S. Jecker, Jonathan D Katz, Joseph Klein, W. Andrew Kofke, Ruth Landau, Craig D. McClain MD, Alex Mauron, Kelly N. Michelson, Cynthiane J. Morgenweck, William Notcutt, Michael Nurok, Susan K. Palmer, Joan G. Quaine, Michael A. Rie, Stanley H. Rosenbaum, David M. Rothenberg, Robert B. Schonberger, Mark D. Siegel, Jeffrey H. Silverstein, Murali Sivarajan, Karen Souter MD, Thomas Specht MD, Andrea Trescot, Gail A. Van Norman, A.M. Viens, Elizabeth K. Vig, David B. Waisel, Clarence Ward, James M. West, Richard L Wolman, Steve Yentis
- Edited by Gail A. Van Norman, University of Washington, Stephen Jackson, Stanley H. Rosenbaum, Susan K. Palmer
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- Book:
- Clinical Ethics in Anesthesiology
- Published online:
- 05 March 2012
- Print publication:
- 28 October 2010, pp xi-xiv
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. Nicholson, George W. E. Nickelsburg, Tatyana Nikolskaya, Damayanthi M. A. Niles, Bertil Nilsson, Nyambura Njoroge, Fidelis Nkomazana, Mary Beth Norton, Christian Nottmeier, Sonene Nyawo, Anthère Nzabatsinda, Edward T. Oakes, Gerald O'Collins, Daniel O'Connell, David W. Odell-Scott, Mercy Amba Oduyoye, Kathleen O'Grady, Oyeronke Olajubu, Thomas O'Loughlin, Dennis T. Olson, J. Steven O'Malley, Cephas N. Omenyo, Muriel Orevillo-Montenegro, César Augusto Ornellas Ramos, Agbonkhianmeghe E. Orobator, Kenan B. Osborne, Carolyn Osiek, Javier Otaola Montagne, Douglas F. Ottati, Anna May Say Pa, Irina Paert, Jerry G. Pankhurst, Aristotle Papanikolaou, Samuele F. Pardini, Stefano Parenti, Peter Paris, Sung Bae Park, Cristián G. Parker, Raquel Pastor, Joseph Pathrapankal, Daniel Patte, W. Brown Patterson, Clive Pearson, Keith F. Pecklers, Nancy Cardoso Pereira, David Horace Perkins, Pheme Perkins, Edward N. Peters, Rebecca Todd Peters, Bishop Yeznik Petrossian, Raymond Pfister, Peter C. Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. 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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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Bahamian giant stromatolites: microbial composition of surface mats
- Robert Riding, Stanley M. Awramik, Barbara M. Winsborough, Karen M. Griffin, Robert F. Dill
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- Geological Magazine / Volume 128 / Issue 3 / May 1991
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- 01 May 2009, pp. 227-234
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Subtidal columnar stromatolites up to 2.5 m high near Lee Stocking Island in the Exuma Cays, Bahamas, have surface mats approximately equally composed of algae and cyanobacteria. The stromatolites are composed of fine–medium oöid and peloid sand. This sediment is supplied to the growing stromatolite surfaces by strong tidal currents which lift grains into suspension and sweep migrating dunes over the columns. The algae include an unidentified filamentous chlorophyte, and numerous diatom species mostly belonging to Mastogloia, Nitzschia and Navicula. The dominant cyanobacteria are two oscillatoriacean species, both probably belonging to Schizothrix. Trapping of sediment is mainly effected by the unidentified chlorophyte which is veneered by epiphytic diatoms. Grains are bound into a mucilaginous mat composed of diatoms and cyanobacteria. Cyanobacteria alone would not be able to trap and bind coarse sediment so effectively in this environment. In being coarse-grained and having a significant eualgal component to their mats, these stromatolites are similar to subtidal columnar stromatolites at Shark Bay, Western Australia. The Lee Stocking stromatolites are physically stressed by high velocity tidal currents and mobile sediment. The Shark Bay stromatolites are stressed by hypersalinity. In both cases stress deters grazers, encrusters and bioeroders. These coarse-grained eualgal stromatolites contrast with micritic and predominantly prokaryotic stromatolites of most Recent marine environments, and are not analogues for most pre-Phanerozoic stromatolites. They appear to be a response to changing stromatolitic mat components in the Cenozoic.
INTER-DIVISION IV-V / WORKING GROUP ACTIVE B-TYPE STARS
- Juan Fabregat, Geraldine J. Peters, Stanley P. Owocki, Karen S. Bjorkman, Douglas R. Gies, Hubertus F. Henrichs, David A. McDavid, Coralie Neiner, Philippe Stee
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- Proceedings of the International Astronomical Union / Volume 4 / Issue T27A / December 2008
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- 01 December 2008, pp. 242-244
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- December 2008
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The Working Group on Active B-type Stars (formerly known as the Working Group on Be Stars) was re-established under IAU Commission 29 at the IAU General Assembly in Montreal, Quebec (Canada) in 1979, and has been continuously active to the present. Its main goal is to promote and stimulate research and international collaboration on the field of the active early-type (OB) stars.
Antibiotic Exposure and Room Contamination Among Patients Colonized With Vancomycin-Resistant Enterococci
- Marci Drees, David R. Snydman, Christopher H. Schmid, Laurie Barefoot, Karen Hansjosten, Padade M. Vue, Michel Cronin, Stanley A. Nasraway, Yoav Golan
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 29 / Issue 8 / August 2008
- Published online by Cambridge University Press:
- 02 January 2015, pp. 709-715
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- August 2008
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Objective.
To determine whether total and antianaerobic antibiotic exposure increases the risk of room contamination among vancomycin-resistant enterococci (VRE)–colonized patients.
Design And Setting.A 14-month study in 2 intensive care units at an academic tertiary care hospital in Boston, Massachusetts.
Patients.All patients who acquired VRE or were VRE-colonized on admission and who had environmental cultures performed.
Methods.We performed weekly environmental cultures (2 sites per room) and considered a room to be contaminated if there was a VRE-positive environmental culture during the patient's stay. We determined risk factors for room contamination by use of the Cox proportional hazards model.
Results.Of 142 VRE-colonized patients, 35 (25%) had an associated VRE-positive environmental culture. Patients who contaminated their rooms were more likely to have diarrhea than those who did not contaminate their rooms (23 [66%] of 35 vs 41 [38%] of 107; P = .005) and more likely to have received antibiotics while VRE colonized (33 [94%] of 35 vs 86 [80%] of 107; P = .02). There was no significant difference in room contamination rates between patients exposed to antianaerobic regimens and patients exposed to nonantianaerobic regimens or between patients with and patients without diarrhea, but patients without any antibiotic exposure were unlikely to contaminate their rooms. Diarrhea and antibiotic use were strongly confounded; although two-thirds of room contamination occurred in rooms of patients with diarrhea, nearly all of these patients received antibiotics. In multivariable analysis, higher mean colonization pressure in the ICU increased the risk of room contamination (adjusted hazard ratio per 10% increase, 1.44 [95% confidence interval, 1.04–2.04]), whereas no antibiotic use during VRE colonization was protective (adjusted hazard ratio, 0.21 [95% confidence interval, 0.05–0.89]).
Conclusions.Room contamination with VRE was associated with increased mean colonization pressure in the ICU and diarrhea in the VRE-colonized patient, whereas no use of any antibiotics during VRE colonization was protective.
Dietary effects on the microbiological safety of food
- E. Carol McWilliam Leitch, Sylvia H. Duncan, Karen N. Stanley, Colin S. Stewart
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- Proceedings of the Nutrition Society / Volume 60 / Issue 2 / May 2001
- Published online by Cambridge University Press:
- 28 February 2007, pp. 247-255
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The high mortality rate associated with human infections caused by Escherichia coli strains of the serotype O157:H7 has brought to public attention the importance of ruminants as reservoirs of food-borne pathogens. In addition to established examples such as salmonella, campylobacter and listeria, recent evidence is emerging of the role of food in the transmission of Helicobacter pylori and Mycobacterium paratuberculosis. Food-borne pathogens harboured by ruminants are spread through shedding in the faeces and subsequent faecal contamination of raw food. Ruminant shedding appears to be affected by diet and, of particular concern, may be increased during fasting regimens imposed during transport to the slaughterhouse. The survival of food-borne pathogens in the ruminant gut is affected by many factors including microbe–microbe interactions, interactions involving plant metabolites and the presence of inhibitory end-product metabolites such as short-chain fatty acids. The potential importance of digesta flow and bacterial detachment in shedding of food-borne pathogens is discussed. Experimental procedures with dangerous pathogens have constraints, particularly in animal experimentation. This situation may be overcome by the use of rumen-simulating fermentors. One such system which, like the natural rumen, has a different turnover rate for solid and liquid digesta, was found to maintain rumen-like variables over an 11 d period. This system may prove useful for the study of dietary effects on food-borne pathogens.
Effects of esculin and esculetin on the survival of Escherichia coli O157 in human faecal slurries, continuous-flow simulations of the rumen and colon and in calves
- Sylvia H. Duncan, E. Carol McWilliam Leitch, Karen N. Stanley, Anthony J. Richardson, Richard A. Laven, Harry J. Flint, Colin S. Stewart
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- Journal:
- British Journal of Nutrition / Volume 91 / Issue 5 / May 2004
- Published online by Cambridge University Press:
- 09 March 2007, pp. 749-755
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- May 2004
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The human pathogen Escherichia coli O157:H7 is thought to be spread by direct or indirect contact with infected animal or human faeces. The present study investigated the effects of the plant coumarin esculin and its aglycone esculetin on the survival of a strain of E. coli O157 under gut conditions. The addition of these compounds to human faecal slurries and in vitro continuous-flow fermenter models simulating conditions in the human colon and rumen caused marked decreases in the survival of an introduced strain of E. coli O157. When four calves were experimentally infected with E. coli O157 and fed esculin, the pathogen was detected in five of twenty-eight (18 %) of faecal samples examined post-inoculation, compared with thirteen of thirty-five (37 %) of faecal samples examined from five control calves not fed esculin. Coumarin compounds that occur naturally in dietary plants or when supplemented in the diet probably inhibit the survival of E. coli O157 in the gut.
Lateral Variation in the Schottky Barrier Height and Observation of Critical Lengths at Au/PtSi/(100)Si and Au/(100)GaAs Diodes
- A. Alec Talin, Tue Ngo, R. Stanley Williams, Brent A. Morgan, Ken M. Ring, Karen L. Kavanagh
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- Journal:
- MRS Online Proceedings Library Archive / Volume 337 / 1994
- Published online by Cambridge University Press:
- 25 February 2011, 319
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- 1994
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Lateral variations in the Schottky barrier height (SBH) formed at Au/PtSi/(100)Si and Au/(100)GaAs diodes were measured on length scales ranging from a few to several hundred nanometers using ballistic electron emission microscopy (BEEM). All of the contacts investigated showed SBH spatial inhomogeneity. The most severe SBH variations observed were 0.09eV/0.7nm in Au/(100)GaAs contacts and 0.08eV/14nm for Au/PtSi/(100)Si contacts. Based on the lateral maps of the SBH at each interface, the difference between the locally averaged SBH and the globally averaged BEEM SBH was computed. This analysis showed that there is a critical diode length scale below which the SBH deviates significantly from the SBH averaged over a macroscopic length scale. This result implies that the uniformity of electrical characteristics of arrays of small devices (e.g.. PtSi/Si photodetectors and GaAs FET gates) can be expected to deteriorate significantly when device dimensions decrease below the critical length.
Beem Investigation of Oxide and Sulfide Passivated GaAs
- A. Alec Talin, R. Stanley Williams, Karen L. Kavanagh
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- MRS Online Proceedings Library Archive / Volume 281 / 1992
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- 25 February 2011, 653
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- 1992
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Ballistic Electron Emission Microscopy (BEEM) was used to investigate the effects of a sulfide interfacial layer on the electronic properties of the Au/n-GaAs interface. Two diodes were simultaneously prepared in UHV by evaporating Au onto (100)GaAs substrates which were either treated with (NH4)2S or NH4OH etching solutions prior to Au deposition. Auger electron spectroscopy was used in situ to monitor the surface chemical composition. The effective Schottky barrier (SB) height was measured with BEEM at 10 different locations on the surface of each diode. The (NH4)2S treatment increased the average barrier height and reduced the spread in the values, as compared to the contact formed on the NH4OH treated GaAs.