9 results
8 Detection of Feigned ADHD through an Experimental MMPI-2 ADHD Validity Scale among U.S. Military Veterans
- Christopher T. Burley, Timothy J. Arentsen, Jennifer S. Seeley McGee, Katie M. Califano, Holly R. Winiarski, Marcy C. Adler, Brad L. Roper
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 693-694
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Objective:
The prevalence of ADHD diagnoses more than doubled in VA settings between 2009 and 2016 (Hale et al., 2020). However, attentional difficulties are not exclusive to ADHD and can also be seen in non-neurodevelopmental disorders, including depression, anxiety, substance use, and PTSD (Marshall et al., 2018, Suhr et al., 2008). Further, patients can easily feign symptoms of ADHD with few available instruments for accurate detection (Robinson & Rogers, 2018). Given the significant symptom overlap and rising rates of reported ADHD among Veterans, accurate detection of feigned ADHD is essential.
This study examined the utility of the experimental Dissimulation ADHD scale (Ds-ADHD; Robinson & Rogers, 2018) on the MMPI-2, in detecting feigned ADHD presentation within a mixed sample of Veterans.
Participants and Methods:In this retrospective study, 173 Veterans (Mage = 36.18, SDage = 11.10, Medu = 14.01, SDedu = 2.11, 88% male, 81% White, and 17% Black) were referred for neuropsychological evaluation of ADHD that included the MMPI-2 and up to 10 PVTs. Participants were assigned to a credible group (n=146) if they passed all PVTs or a non-credible group (n=27) if they failed two or more PVTs. Group assignment was also clinically confirmed. The Ds-ADHD was used to differentiate groups who either had credible or non-credible performance on cognitive measures. Consistent with Robinson and Rogers’ study, “true” answers (i.e., erroneous stereotypes) were coded as 1 and “false” answers were coded as 2, creating a 10- to 20-point scale. Lower scores were associated with a higher likelihood of a feigned ADHD presentation.
Results:Preliminary analyses revealed no significant group differences in age, education, race, or gender (ps > .05). An ANOVA indicated a significant difference between groups (F[1, 171] = 10.44, p = .001; Cohen’s d = .68) for Ds-ADHD raw scores; Veterans in the non-credible group reported more “erroneous stereotypes” of ADHD (M raw score = 13.33, SD = 2.20) than those in the credible group (M = 14.82, SD = 2.20). A ROC analysis indicated AUC of .691 (95% CI = .58 to .80). In addition, a cut score of <12 resulted in specificity of 91.8% and sensitivity of 18.5%, whereas a cut score of <13 resulted in specificity of 83.6% and sensitivity of 44.4%.
Conclusions:The Ds-ADHD scale demonstrated significant differences between credible and non-credible respondents in a real-world setting. Previously, this scale has primarily been studied within laboratory settings. Further, results indicate a cut score of <12 could be used in order to achieve adequate specificity (i.e., >90%), which were similar findings to a study examining SVT-based groups (Winiarski et al., 2023). These results differ slightly from prior research by Robinson and Rogers (2018), who indicated a cut score of <13 based on the initial simulation-based study. In similar clinical settings, where there are high rates of psychiatric comorbidity, a cut score of <12 may prove clinically useful. However, this cut-score was associated with low sensitivity within this mixed Veteran sample. Further research should focus on replicating findings within other clinical settings, including ones with larger non-credible samples.
20 Clinical Utility of an Experimental Ds-ADHD Validity Scale in Detection of Feigned ADHD symptoms in a U.S. Military Population
- Holly R Winiarski, Timothy J Arentsen, Marcy C Adler, Christopher T Burley, Katie M Califano, Jennifer S Seeley-McGee, Brad L Roper
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, p. 703
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Objective:
Accurate identification of Attention-Deficit/Hyperactivity Disorder (ADHD) is complicated by possible secondary gain, overlap of symptoms with psychiatric disorders, and face validity of measures (Suhr et al., 2011; Shura et al., 2017). To assist with diagnostic clarification, an experimental Dissimulation ADHD scale (Ds-ADHD; Robinson & Rogers, 2018) on the MMPI-2 was found to distinguish credible from non-credible respondents defined by Performance Validity Test (PVT)-based group assignment in Veterans (Burley et al., 2023). However, symptom and performance validity have been understood as unique constructs (Van Dyke et al., 2013), with Symptom Validity Tests (SVTs) more accurately identifying over-reporting of symptoms in ADHD (White et al., 2022). The current study sought to evaluate the effectiveness of the Ds-ADHD scale using an SVT, namely the Infrequency Index of CAARS (CII; Suhr et al., 2011), for group assignment within a mixed sample of Veterans.
Participants and Methods:In this retrospective study, 187 Veterans (Mage = 36.76, SDage = 11.25, Medu = 14.02, SDedu = 2.10, 83% male, 19% black, 78% white) were referred for neuropsychological evaluation of ADHD and administered a battery that included internally consistent MMPI-2 and CAARS profiles. Veterans were assigned to a credible group (n=134) if CII was <21 or a non-credible group (n=53) if CII was >21. The Ds-ADHD scale was calculated for the MMPI-2. Consistent with Robinson and Rogers (2018), “true” answers (i.e., erroneous stereotypes) were coded as 1 and “false” answers were coded as 2, creating a 10- to 20-point scale. Lower scores were associated with a higher likelihood of a feigned ADHD presentation.
Results:Analyses revealed no significant differences in age, education, race, or gender (ps > .05) between credible and non-credible groups. An ANOVA indicated a significant difference between groups (F[1,185] = 24.78, p <.001; Cohen’s d = 0.80) for Ds-ADHD raw scores. Veterans in the non-credible group reported more “erroneous stereotypes” of ADHD (M raw score = 13.23, SD = 2.10) than those in the credible group (M = 14.94, SD = 2.13). A ROC analysis indicated AUC of .72 (95% CI = .64 to .80). In addition, a Ds-ADHD cut score of <12 resulted in specificity of 94.5% and sensitivity of 22.6%, whereas a cut score of <13 resulted in specificity of 85.8% and sensitivity of 50.9%. When analyzing other CII cut scores recommended in the literature, results were essentially similar. Specifically, analyses were repeated when group assignment was defined by cut score of CII<18 and by removing an intermediate group (CII = 18 to 21; n=24).
Conclusions:The Ds-ADHD scale demonstrated significant differences between credible and non-credible respondents in a Veteran population. Results suggest a cut score of <12 had adequate specificity (.95) with low sensitivity (.23). This is consistent with findings using PVTs for group assignment that indicated a cut score of <12 had adequate specificity (.92) with low sensitivity (.19; Burley et al., 2023). Taken together, findings suggest that the Ds-ADHD scale demonstrates utility in the dissociation of credible from non-credible responding. Further research should evaluate the utility of the scale in other clinical populations.
31 The ADHD Dissimulation Scale (Ds- ADHD) on the MMPI-2-RF versus Established MMPI-2-RF Validity Scales
- Katie M Califano, Timothy J Arentsen, Holly R Winiarski, Christopher T Burley, Marcy C Adler, Jennifer S Seeley McGee, Brad L Roper
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 712-713
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Objective:
The MMPI-2-RF contains scales that assess different types of invalid response styles, especially potential symptom over-reporting (e.g., F-r, Fs, Fp-r, FBS-r, RBS). However, these scales are not designed to specifically capture noncredible symptoms reports associated with Attention-Deficit/Hyperactivity Disorder (ADHD). Robinson & Rogers (2018) proposed the experimental Dissimulation ADHD validity scale (Ds-ADHD) on the MMPI-2-RF that was effective in distinguishing credible and non-credible ADHD diagnoses via a simulator-based study. Within the current study, the Ds-ADHD scale was compared to the established MMPI-2-RF validity scales within a mixed sample of U.S. Military Veterans.
Participants and Methods:173 Veterans (Mage = 36.18, SDage = 11.10, Medu = 14.01, SDedu = 2.11, 88% male, 81% White, 17% Black) completed a neuropsychological evaluation which included an internally consistent MMPI-2-RF profile and up to 10 performance validity tests (PVTs) as well as a question about a possible ADHD diagnosis. The credible group was determined if participants passed all PVTs (n=146) and completed at least 2 PVTs. The non-credible group was determined by failing two or more PVTs (n=27). Group assignment was clinically confirmed. The Ds-ADHD scale was calculated according to Robinson & Rogers’ (2018); responses of “true” (i.e., erroneous stereotypes) were coded as 1 and “false” answers were coded 2, creating a 10- to 20-point scale. Thus, lower scores would be associated with a higher likelihood of a feigned ADHD presentation. Other MMPI-2-RF validity scales of interest included F-r, Fs, Fp-r, FBS-r, and RBS.
Results:The established MMPI-2-RF validity scales were significantly correlated with PVT group membership, but correlations were weak to moderately strong (rS ranged from -.43 to -.18; ps < .05). A series of stepwise regression models were completed with the Ds-ADHD scale and one of the MMPI-2-RF validity scales as independent variables, with group membership as the dependent variable. Ds-ADHD) contributed uniquely to each model (CÜ ranged from .03 to .04, ps < .05). The established MMPI-2-RF validity scales effectively classified group membership (AUC values ranged from .57 to .68), and the Ds-ADHD scale had a marginally higher AUC (.69); however, it was not statistically significantly stronger than any of the established scales (ps > .05).
Conclusions:Clinicians interested in identifying potentially simulated ADHD presentations with the MMPI-2-RF may desire to calculate the Ds-ADHD scale, which previously only had support from a simulator-based study. The Ds-ADHD scale significantly contributed to each model, suggesting that it helped explain groups over and above each of the traditional MMPI-2-RF validity scales. However, it only had a marginally stronger ability to classify participants, indicating that there may be diminishing returns for clinicians. Among the traditional validity scales, RBS and F-r best classified groups, and FBS-r was the least effective. This study employed a cross-sectional design in a mixed sample of Veterans undergoing a neuropsychological evaluation. Future research should focus on replicating the findings using a credible sample that was limited to an independently verified diagnosis of ADHD.
Severe acute respiratory coronavirus virus 2 (SARS-CoV-2) outbreak investigation in a hospital emergency department—California, December 2020–January 2021
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- Ruoran Li, Elizabeth Beshearse, Deborah Malden, Holly Truong, Vit Kraushaar, Brandon J. Bonin, Janice Kim, Idamae Kennedy, Jennifer McNary, George S. Han, Sarah L. Rudman, Joseph F. Perz, Kiran M. Perkins, Janet Glowicz, Erin Epson, Isaac Benowitz, Elsa Villarino
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 44 / Issue 7 / July 2023
- Published online by Cambridge University Press:
- 20 May 2022, pp. 1187-1192
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- July 2023
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We describe a large outbreak of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) involving an acute-care hospital emergency department during December 2020 and January 2021, in which 27 healthcare personnel worked while infectious, resulting in multiple opportunities for SARS-CoV-2 transmission to patients and other healthcare personnel. We provide recommendations for improving infection prevention and control.
Optimizing Scarce Resource Allocation During COVID-19: Rapid Creation of a Regional Health-Care Coalition and Triage Teams in San Diego County, California
- Asha Devereaux, Holly Yang, Gilbert Seda, Viji Sankar, Ryan C. Maves, Navaz Karanjia, John Scott Parrish, Christy Rosenberg, Paula Goodman-Crews, Lynette Cederquist, Frederick M. Burkle, Jr., Jennifer Tuteur, Chiara Leroy, Kristi L. Koenig
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- Disaster Medicine and Public Health Preparedness / Volume 16 / Issue 1 / February 2022
- Published online by Cambridge University Press:
- 10 September 2020, pp. 321-327
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Successful management of an event where health-care needs exceed regional health-care capacity requires coordinated strategies for scarce resource allocation. Publications for rapid development, training, and coordination of regional hospital triage teams to manage the allocation of scarce resources during coronavirus disease 2019 (COVID-19) are lacking. Over a period of 3 weeks, over 100 clinicians, ethicists, leaders, and public health authorities convened virtually to achieve consensus on how best to save the most lives possible and share resources. This is referred to as population-based crisis management. The rapid regionalization of 22 acute care hospitals across 4500 square miles in the midst of a pandemic with a shifting regulatory landscape was challenging, but overcome by mutual trust, transparency, and confidence in the public health authority. Because many cities are facing COVID-19 surges, we share a process for successful rapid formation of health-care care coalitions, Crisis Standard of Care, and training of Triage Teams. Incorporation of continuous process improvement and methods for communication is essential for successful implementation. Use of our regional health-care coalition communications, incident command system, and the crisis care committee helped mitigate crisis care in the San Diego and Imperial County region as COVID-19 cases surged and scarce resource collaborative decisions were required.
Deconstructing the externalizing spectrum: Growth patterns of overt aggression, covert aggression, oppositional behavior, impulsivity/inattention, and emotion dysregulation between school entry and early adolescence
- Sheryl L. Olson, Arnold J. Sameroff, Jennifer E. Lansford, Holly Sexton, Pamela Davis-Kean, John E. Bates, Gregory S. Pettit, Kenneth A. Dodge
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- Development and Psychopathology / Volume 25 / Issue 3 / August 2013
- Published online by Cambridge University Press:
- 23 July 2013, pp. 817-842
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The purpose of this study was to determine whether five subcomponents of children's externalizing behavior showed distinctive patterns of long-term growth and predictive correlates. We examined growth in teachers' ratings of overt aggression, covert aggression, oppositional defiance, impulsivity/inattention, and emotion dysregulation across three developmental periods spanning kindergarten through Grade 8 (ages 5–13 years). We also determined whether three salient background characteristics, family socioeconomic status, child ethnicity, and child gender, differentially predicted growth in discrete categories of child externalizing symptoms across development. Participants were 543 kindergarten-age children (52% male, 81% European American, 17% African American) whose problem behaviors were rated by teachers each successive year of development through Grade 8. Latent growth curve analyses were performed for each component scale, contrasting with overall externalizing, in a piecewise fashion encompassing three developmental periods: kindergarten–Grade 2, Grades 3–5, and Grades 6–8. We found that most subconstructs of externalizing behavior increased significantly across the early school age period relative to middle childhood and early adolescence. However, overt aggression did not show early positive growth, and emotion dysregulation significantly increased across middle childhood. Advantages of using subscales were most clear in relation to illustrating different growth functions between the discrete developmental periods. Moreover, growth in some discrete subcomponents was differentially associated with variations in family socioeconomic status and ethnicity. Our findings strongly affirmed the necessity of adopting a developmental approach to the analysis of growth in children's externalizing behavior and provided unique data concerning similarities and differences in growth between subconstructs of child and adolescent externalizing behavior.
Use of vitamin D supplements during infancy in an international feeding trial
- Eveliina Lehtonen, Anne Ormisson, Anita Nucci, David Cuthbertson, Susa Sorkio, Mila Hyytinen, Kirsi Alahuhta, Carol Berseth, Marja Salonen, Shayne Taback, Margaret Franciscus, Teba González-Frutos, Tuuli E Korhonen, Margaret L Lawson, Dorothy J Becker, Jeffrey P Krischer, Mikael Knip, Suvi M Virtanen, , Thomas Mandrup-Poulsen, Elias Arjas, Åke Lernmark, Barbara Schmidt, Jeffrey P. Krischer, Hans K. Åkerblom, Mila Hyytinen, Mikael Knip, Katriina Koski, Matti Koski, Eeva Pajakkala, Marja Salonen, David Cuthbertson, Jeffrey P. Krischer, Linda Shanker, Brenda Bradley, Hans-Michael Dosch, John Dupré, William Fraser, Margaret Lawson, Jeffrey L. Mahon, Mathew Sermer, Shayne P. Taback, Dorothy Becker, Margaret Franciscus, Anita Nucci, Jerry Palmer, Minna Pekkala, Suvi M. Virtanen, Jacki Catteau, Neville Howard, Patricia Crock, Maria Craig, Cheril L. Clarson, Lynda Bere, David Thompson, Daniel Metzger, Colleen Marshall, Jennifer Kwan, David K. Stephure, Daniele Pacaud, Wendy Schwarz, Rose Girgis, Marilyn Thompson, Shayne P. Taback, Daniel Catte, Margaret L. Lawson, Brenda Bradley, Denis Daneman, Mathew Sermer, Mary-Jean Martin, Valérie Morin, Lyne Frenette, Suzanne Ferland, Susan Sanderson, Kathy Heath, Céline Huot, Monique Gonthier, Maryse Thibeault, Laurent Legault, Diane Laforte, Elizabeth A. Cummings, Karen Scott, Tracey Bridger, Cheryl Crummell, Robyn Houlden, Adriana Breen, George Carson, Sheila Kelly, Koravangattu Sankaran, Marie Penner, Richard A. White, Nancy King, James Popkin, Laurie Robson, Eva Al Taji, Irena Aldhoon, Pavla Mendlova, Jan Vavrinec, Jan Vosahlo, Ludmila Brazdova, Jitrenka Venhacova, Petra Venhacova, Adam Cipra, Zdenka Tomsikova, Petra Krckova, Pavla Gogelova, Ülle Einberg, Mall-Anne Riikjärv, Anne Ormisson, Vallo Tillmann, Päivi Kleemola, Anna Parkkola, Heli Suomalainen, Anna-Liisa Järvenpää, Anu-Maaria Hämälainen, Hannu Haavisto, Sirpa Tenhola, Pentti Lautala, Pia Salonen, Susanna Aspholm, Heli Siljander, Carita Holm, Samuli Ylitalo, Raisa Lounamaa, Anja Nuuja, Timo Talvitie, Kaija Lindström, Hanna Huopio, Jouni Pesola, Riitta Veijola, Päivi Tapanainen, Abram Alar, Paavo Korpela, Marja-Liisa Käär, Taina Mustila, Ritva Virransalo, Päivi Nykänen, Bärbel Aschemeier, Thomas Danne, Olga Kordonouri, Dóra Krikovszky, László Madácsy, Yeganeh Manon Khazrai, Ernesto Maddaloni, Paolo Pozzilli, Carla Mannu, Marco Songini, Carine de Beaufort, Ulrike Schierloh, Jan Bruining, Margriet Bisschoff, Aleksander Basiak, Renata Wasikowa, Marta Ciechanowska, Grazyna Deja, Przemyslawa Jarosz-Chobot, Agnieszka Szadkowska, Katarzyna Cypryk, Malgorzata Zawodniak-Szalapska, Luis Castano, Teba Gonzalez Frutos, Mirentxu Oyarzabal, Manuel Serrano-Ríos, María Teresa Martínez-Larrad, Federico Gustavo Hawkins, Dolores Rodriguez Arnau, Johnny Ludvigsson, Malgorzata Smolinska Konefal, Ragnar Hanas, Bengt Lindblad, Nils-Osten Nilsson, Hans Fors, Maria Nordwall, Agne Lindh, Hans Edenwall, Jan Aman, Calle Johansson, Margrit Gadient, Eugen Schoenle, Dorothy Becker, Ashi Daftary, Margaret Franciscus, Carol Gilmour, Jerry Palmer, Rachel Taculad, Marilyn Tanner-Blasiar, Neil White, Uday Devaskar, Heather Horowitz, Lisa Rogers, Roxana Colon, Teresa Frazer, Jose Torres, Robin Goland, Ellen Greenberg, Maudene Nelson, Holly Schachner, Barney Softness, Jorma Ilonen, Massimo Trucco, Lynn Nichol, Erkki Savilahti, Taina Härkönen, Mikael Knip, Outi Vaarala, Kristiina Luopajärvi, Hans-Michael Dosch
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- Journal:
- Public Health Nutrition / Volume 17 / Issue 4 / April 2014
- Published online by Cambridge University Press:
- 24 June 2013, pp. 810-822
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Objective
To examine the use of vitamin D supplements during infancy among the participants in an international infant feeding trial.
DesignLongitudinal study.
SettingInformation about vitamin D supplementation was collected through a validated FFQ at the age of 2 weeks and monthly between the ages of 1 month and 6 months.
SubjectsInfants (n 2159) with a biological family member affected by type 1 diabetes and with increased human leucocyte antigen-conferred susceptibility to type 1 diabetes from twelve European countries, the USA, Canada and Australia.
ResultsDaily use of vitamin D supplements was common during the first 6 months of life in Northern and Central Europe (>80 % of the infants), with somewhat lower rates observed in Southern Europe (>60 %). In Canada, vitamin D supplementation was more common among exclusively breast-fed than other infants (e.g. 71 % v. 44 % at 6 months of age). Less than 2 % of infants in the USA and Australia received any vitamin D supplementation. Higher gestational age, older maternal age and longer maternal education were study-wide associated with greater use of vitamin D supplements.
ConclusionsMost of the infants received vitamin D supplements during the first 6 months of life in the European countries, whereas in Canada only half and in the USA and Australia very few were given supplementation.
Contributors
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- By Nalini Vadivelu, Christian J. Whitney, Raymond S. Sinatra, M. Khurram Ghori, Yu-Fan (Robert) Zhang, Raymond S. Sinatra, Joshua Wellington, Yuan-Yi Chia, Francis J. Keefe, Jon McCormack, Ian Power, John Butterworth, P. M. Lavand’homme, M. F. De Kock, Bradley Urie, Oscar A. de Leon-Casasola, Frederick M. Perkins, Larry F. Chu, David Clark, Martin S. Angst, Cynthia M. Welchek, Lisa Mastrangelo, Raymond S. Sinatra, Richard Martinez, Scott S. Reuben, Asokumar Buvanendran, Raymond S. Sinatra, Pamela E Macintyre, Julia Coldrey, Daniel B. Maalouf, Spencer S. Liu, Susan Dabu-Bondoc, Samantha A. Franco, Raymond S. Sinatra, James Benonis, Jennifer Fortney, David Hardman, Gavin Martin, Holly Evans, Karen C. Nielsen, Marcy S. Tucker, Stephen M. Klein, Benjamin Sherman, Ikay Enu, Raymond S. Sinatra, James W. Heitz, Eugene R. Viscusi, Jonathan S. Jahr, Kofi N. Donkor, Raymond S. Sinatra, Manzo Suzuki, Johan Raeder, Vegard Dahl, Stefan Erceg, Keun Sam Chung, Kok-Yuen Ho, Tong J. Gan, Dermot R. Fitzgibbon, Paul Willoughby, Brian E. Harrington, Joseph Marino, Tariq M. Malik, Raymond S. Sinatra, Giorgio Ivani, Valeria Mossetti, Simona Italiano, Thomas M. Halaszynski, Nousheh Saidi, Javier Lopez, Kate Miller, Ferne Braveman, Jaya L. Varadarajan, Steven J. Weisman, Sukanya Mitra, Raymond S. Sinatra, Theodore J. Saclarides, Knox H. Todd, James R. Miner, Chris Pasero, Nancy Eksterowicz, Margo McCaffery, Leslie N. Schechter, Amr E. Abouleish, Govindaraj Ranganathan, Tee Yong Tan, Stephan A. Schug, Marie N. Hanna, Spencer S. Liu, Christopher L. Wu, Craig T. Hartrick, Garen Manvelian, Christine Miaskowski, Brian Durkin, Peter S. A. Glass
- Edited by Raymond S. Sinatra, Oscar A. de Leon-Cassasola, University of Rochester Medical Center, New York, Eugene R. Viscusi, Brian Ginsberg
- Foreword by Henry McQuay
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- Book:
- Acute Pain Management
- Published online:
- 26 October 2009
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- 27 April 2009, pp vii-xii
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Properties of Plutonium-Containing Colloids Released from Glass-Bonded Sodalite Nuclear Waste form
- Lester R. Morss, Carol J. Mertz, A. Jeremy Kropf, Jennifer L. Holly
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- MRS Online Proceedings Library Archive / Volume 713 / 2002
- Published online by Cambridge University Press:
- 21 March 2011, JJ6.6
- Print publication:
- 2002
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In glass-bonded sodalite, which is the ceramic waste form (CWF) to immobilize radioactive electrorefiner salt from spent metallic reactor fuel, uranium and plutonium are found as 20-50 nm (U,Pu)O2 particles encapsulated in glass near glass-sodalite phase boundaries. In order to determine whether the (U,Pu)O2 affects the durability of the CWF, and to determine release behavior of uranium and plutonium during CWF corrosion, tests were conducted to measure the release of matrix and radioactive elements from crushed CWF samples into water and the properties of released plutonium. Released colloids have been characterized by sequential filtration of test solutions followed by elemental analysis, dynamic light scattering, transmission electron microscopy (TEM), and X-ray absorption spectroscopy. This paper reports the composition, size, and agglomeration of these colloids. Significant amounts of colloidal, amorphous aluminosilicates and smaller amounts of colloidal crystalline (U,Pu)O2 were identified in test solutions. The normalized releases of uranium and plutonium were significantly less than the normalized releases of matrix elements, i.e., the CWF retains these radionuclides well.