19 results
Estimating minimum dietary diversity for children aged 6–23 months: a comparison of agreement and cost of two recall methods in Cambodia and Zambia
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- Laura S Hackl, Lidan Du-Skabrin, Amry Ok, Chiza Kumwenda, Navy Sin, Lukonde Mwelwa-Zgambo, Ramji Dhakal, Bubala Thandie Hamaimbo, Elise C Reynolds, Katherine P Adams, Charles D Arnold, Christine P Stewart, Erin M Milner, Sarah Pedersen, Jennifer Yourkavitch
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- Journal:
- Public Health Nutrition / Volume 27 / Issue 1 / 2024
- Published online by Cambridge University Press:
- 22 January 2024, e79
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Objective:
To compare the agreement and cost of two recall methods for estimating children’s minimum dietary diversity (MDD).
Design:We assessed child’s dietary intake on two consecutive days: an observation on day one, followed by two recall methods (list-based recall and multiple-pass recall) administered in random order by different enumerators at two different times on day two. We compared the estimated MDD prevalence using survey-weighted linear probability models following a two one-sided test equivalence testing approach. We also estimated the cost-effectiveness of the two methods.
Setting:Cambodia (Kampong Thom, Siem Reap, Battambang, and Pursat provinces) and Zambia (Chipata, Katete, Lundazi, Nyimba, and Petauke districts).
Participants:Children aged 6–23 months: 636 in Cambodia and 608 in Zambia.
Results:MDD estimations from both recall methods were equivalent to the observation in Cambodia but not in Zambia. Both methods were equivalent to the observation in capturing most food groups. Both methods were highly sensitive although the multiple-pass method accurately classified a higher proportion of children meeting MDD than the list-based method in both countries. Both methods were highly specific in Cambodia but moderately so in Zambia. Cost-effectiveness was better for the list-based recall method in both countries.
Conclusion:The two recall methods estimated MDD and most other infant and young child feeding indicators equivalently in Cambodia but not in Zambia, compared to the observation. The list-based method produced slightly more accurate estimates of MDD at the population level, took less time to administer and was less costly to implement.
The cost-effectiveness of small-quantity lipid-based nutrient supplements for prevention of child death and malnutrition and promotion of healthy development: modelling results for Uganda
- Katherine P Adams, Stephen A Vosti, Charles D Arnold, Reina Engle-Stone, Elizabeth L Prado, Christine P Stewart, K Ryan Wessells, Kathryn G Dewey
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- Journal:
- Public Health Nutrition / Volume 26 / Issue 10 / October 2023
- Published online by Cambridge University Press:
- 22 August 2023, pp. 2083-2095
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Objective:
Recent meta-analyses demonstrate that small-quantity lipid-based nutrient supplements (SQ-LNS) for young children significantly reduce child mortality, stunting, wasting, anaemia and adverse developmental outcomes. Cost considerations should inform policy decisions. We developed a modelling framework to estimate the cost and cost-effectiveness of SQ-LNS and applied the framework in the context of rural Uganda.
Design:We adapted costs from a costing study of micronutrient powder (MNP) in Uganda, and based effectiveness estimates on recent meta-analyses and Uganda-specific estimates of baseline mortality and the prevalence of stunting, wasting, anaemia and developmental disability.
Setting:Rural Uganda.
Participants:Not applicable.
Results:Providing SQ-LNS daily to all children in rural Uganda (> 1 million) for 12 months (from 6 to 18 months of age) via the existing Village Health Team system would cost ∼$52 per child (2020 US dollars) or ∼$58·7 million annually. SQ-LNS could avert an average of > 242 000 disability-adjusted life years (DALYs) annually as a result of preventing 3689 deaths, > 160 000 cases of moderate or severe anaemia and ∼6000 cases of developmental disability. The estimated cost per DALY averted is $242.
Conclusions:In this context, SQ-LNS may be more cost-effective than other options such as MNP or the provision of complementary food, although the total cost for a programme including all age-eligible children would be high. Strategies to reduce costs, such as targeting to the most vulnerable populations and the elimination of taxes on SQ-LNS, may enhance financial feasibility.
Cross-shore wind-induced changes to field-scale overturning wave shape
- Falk Feddersen, Adam M. Fincham, Katherine L. Brodie, Adam P. Young, M.S. Spydell, Derek J. Grimes, Michal Pieszka, Kentaro Hanson
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- Journal:
- Journal of Fluid Mechanics / Volume 958 / 10 March 2023
- Published online by Cambridge University Press:
- 27 February 2023, A4
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The shape of depth-limited breaking-wave overturns is important for turbulence injection, bubble entrainment and sediment suspension. Overturning wave shape depends on a nonlinearity parameter $H/h$, where $H$ is the wave height, and $h$ is the water depth. Cross-shore wind direction (offshore/onshore) and magnitude affect laboratory shoaling wave shape and breakpoint location $X_{{bp}}$, but wind effects on overturning wave shape are largely unstudied. We perform field-scale experiments at the Surf Ranch wave basin with fixed bathymetry and $\approx 2.25$ m shoaling solitons with small height variations propagating at $C=6.7\ \mathrm {m}\ \mathrm {s}^{-1}$. Observed non-dimensional cross-wave wind $U_w$ was onshore and offshore, varying realistically ($-1.2 < U_{w}/C < 0.7$). Georectified images, a wave staff, and lidar are used to estimate $X_{{bp}}$, $H/h$, overturn area $A$ and aspect ratio for 22 waves. The non-dimensionalized $X_{{bp}}$ was inversely related to $U_{w}/C$. The non-dimensional overturn area and aspect ratio also were inversely related to $U_{w}/C$, with smaller and narrower overturns for increasing onshore wind. No overturning shape dependence on the weakly varying $H/h$ was seen. The overturning shape variation was as large as prior laboratory experiments with strong $H/h$ variations without wind. An idealized potential air flow simulation on steep shoaling soliton shape has strong surface pressure variations, potentially inducing overturning shape changes. Through wave-overturning impacts on turbulence and sediment suspension, coastal wind variations could be relevant for near-shore morphology.
Accuracy and cost-effectiveness of the INDDEX24 Dietary Assessment Platform in Viet Nam
- Jennifer Coates, Winnie Bell, Peter Bakun, Katherine P. Adams, Jérome W. Somé, Brooke Colaiezzi, Ha Thi Phuong Do, Beatrice Rogers
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- Journal:
- British Journal of Nutrition / Volume 129 / Issue 10 / 28 May 2023
- Published online by Cambridge University Press:
- 19 May 2022, pp. 1751-1764
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- 28 May 2023
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Technology-enabled approaches to conducting 24-h dietary recalls (24HR) may reduce dietary assessment bottlenecks in low-resource settings. However, few studies have assessed their performance relative to conventional pen-and-paper interview (PAPI) approaches and none have validated performance against a benchmark (e.g. weighed food record (WFR)) in a low- and middle-income country (LMIC). This study assessed relative accuracy and cost-effectiveness of INDDEX24, a technology-enabled approach to conducting 24HR, compared with a PAPI approach and against an observer WFR. Women aged 18–49 years from northern Viet Nam (n 234) were randomly assigned to be interviewed using INDDEX24 or PAPI 24HR following a WFR. The two one-sided t test approach assessed the equivalence of each recall modality to the benchmark. Difference-in-differences analysis compared the recall-benchmark results across modalities. Cost per percentage point of accuracy for INDDEX24 and PAPI was derived from accuracy results and the cost to conduct the 24HR. The PAPI and INDDEX24 24HR were statistically equivalent to the WFR for all nutrients except vitamin A. INDDEX24 diverged significantly less than PAPI from the WFR for Fe (0·9 v. −1·3 mg) and PAPI diverged less for protein (–3·7 v. 7·9 g). At the individual level, 26 % of PAPI and 32 % of INDDEX24 respondents had energy intakes within +/– 10 % of the WFR. INDDEX24 cost $111 004 and the PAPI cost $120 483 (USD 2019), making INDDEX24 more cost-effective across most indicators. INDDEX24 was an accurate and cost-effective method for assessing dietary intake in the study context and represents a preferred alternative to PAPI 24HR in Viet Nam and other LMIC.
The cost and cost efficiency of conducting a 24-h dietary recall using INDDEX24, a mobile dietary assessment platform, compared with pen-and-paper interview in Viet Nam and Burkina Faso
- Katherine P. Adams, Winnie Bell, Jérome W. Somé, Brooke Colaiezzi, Sarah Wafa, Beatrice Rogers, Jennifer Coates
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- Journal:
- British Journal of Nutrition / Volume 129 / Issue 3 / 14 February 2023
- Published online by Cambridge University Press:
- 05 May 2022, pp. 535-549
- Print publication:
- 14 February 2023
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The INDDEX24 Dietary Assessment Platform (INDDEX24) was developed to facilitate the collection of 24-h dietary recall (24HR) data. Alongside validation studies in Viet Nam and Burkina Faso in 2019–2020, we conducted activity-based costing studies to estimate the cost of conducting a 24HR among women of reproductive age using INDDEX24 compared with the pen-and-paper interview (PAPI) approach. We also modelled alternative scenarios in which: (1) 25–75 % of dietary reference data were borrowed from the INDDEX24 Global Food Matters Database (FMDB); (2) all study personnel were locally based and (3) national-scale surveys. In the primary analysis, in Viet Nam, the 24HR cost US $111 004 ($755/respondent, n 147) using INDDEX24 and $120 483 ($820/respondent, n 147) using PAPI. In Burkina Faso, the 24HR cost $78 105 ($539/respondent, n 145) using INDDEX24 and $79 465 ($544/respondent, n 146) using PAPI. In modelled scenarios, borrowing dietary reference data from the FMDB decreased the cost of INDDEX24 by 17–34 % (Viet Nam) and 5–15 % (Burkina Faso). With all locally based personnel, INDDEX24 cost more than PAPI ($498 v. $448 per respondent in Viet Nam and $456 v. $410 in Burkina Faso). However, at national scales (n 4376, Viet Nam; n 6500, Burkina Faso) using all locally based personnel, INDDEX24 was more cost-efficient ($109 v. $137 per respondent in Viet Nam and $123 v. $148 in Burkina Faso). In two countries and under most circumstances, INDDEX24 was less expensive than PAPI. Higher INDDEX24 survey preparation costs (including purchasing equipment) were more than offset by higher PAPI data entry, cleaning and processing costs. INDDEX24 may facilitate cost-efficient dietary data collection.
Systematic review of metrics used to characterise dietary nutrient supply from household consumption and expenditure surveys
- Kevin Tang, Katherine P Adams, Elaine L Ferguson, Monica Woldt, Jennifer Yourkavitch, Sarah Pedersen, Martin R Broadley, Omar Dary, E Louise Ander, Edward JM Joy
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- Journal:
- Public Health Nutrition / Volume 25 / Issue 5 / May 2022
- Published online by Cambridge University Press:
- 13 January 2022, pp. 1153-1165
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Objective:
To review existing publications using Household Consumption and Expenditure Survey (HCES) data to estimate household dietary nutrient supply to (1) describe scope of available literature, (2) identify the metrics reported and parameters used to construct these metrics, (3) summarise comparisons between estimates derived from HCES and individual dietary assessment data and (4) explore the demographic and socio-economic sub-groups used to characterise risks of nutrient inadequacy.
Design:This study is a systematic review of publications identified from online databases published between 2000 to 2019 that used HCES food consumption data to estimate household dietary nutrient supply. Further publications were identified by ‘snowballing’ the references of included database-identified publications.
Setting:Publications using data from low- and lower-middle income countries.
Results:In total, fifty-eight publications were included. Three metrics were reported that characterised household dietary nutrient supply: apparent nutrient intake per adult-male equivalent per day (n 35), apparent nutrient intake per capita per day (n 24) and nutrient density (n 5). Nutrient intakes were generally overestimated using HCES food consumption data, with several studies finding sizeable discrepancies compared with intake estimates based on individual dietary assessment methods. Sub-group analyses predominantly focused on measuring variation in household dietary nutrient supply according to socio-economic position and geography.
Conclusion:HCES data are increasingly being used to assess diets across populations. More research is needed to inform the development of a framework to guide the use of and qualified interpretation of dietary assessments based on these data.
Validation of the INDDEX24 mobile app v. a pen-and-paper 24-hour dietary recall using the weighed food record as a benchmark in Burkina Faso
- Beatrice Rogers, Jérome W. Somé, Peter Bakun, Katherine P. Adams, Winnie Bell, David Alexander Carroll II, Sarah Wafa, Jennie Coates
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- Journal:
- British Journal of Nutrition / Volume 128 / Issue 9 / 14 November 2022
- Published online by Cambridge University Press:
- 26 November 2021, pp. 1817-1831
- Print publication:
- 14 November 2022
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Effective nutrition policies require timely, accurate individual dietary consumption data; collection of such information has been hampered by cost and complexity of dietary surveys and lag in producing results. The objective of this work was to assess accuracy and cost-effectiveness of a streamlined, tablet-based dietary data collection platform for 24-hour individual dietary recalls (24HR) administered using INDDEX24 platform v. a pen-and-paper interview(PAPI) questionnaire, with weighed food record (WFR) as a benchmark. This cross-sectional comparative study included women 18–49 years old from rural Burkina Faso (n 116 INDDEX24; n 115 PAPI). A WFR was conducted; the following day, a 24HR was administered by different interviewers. Food consumption data were converted into nutrient intakes. Validity of 24HR estimates of nutrient and food group consumption was based on comparison with WFR using equivalence tests (group level) and percentages of participants within ranges of percentage error (individual level). Both modalities performed comparably estimating consumption of macro- and micronutrients, food groups and quantities (modalities’ divergence from WFR not significantly different). Accuracy of both modalities was acceptable (equivalence to WFR significant at P < 0·05) at group level for macronutrients, less so for micronutrients and individual-level consumption (percentage within ±20 % for WFR, 17–45 % for macronutrients, 5–17 % for micronutrients). INDDEX24 was more cost-effective than PAPI based on superior accuracy of a composite nutrient intake measure (but not gram amount or item count) due to lower time and personnel costs. INDDEX24 for 24HR dietary surveys linked to dietary reference data shows comparable accuracy to PAPI at lower cost.
Characterisation of age and polarity at onset in bipolar disorder
- Janos L. Kalman, Loes M. Olde Loohuis, Annabel Vreeker, Andrew McQuillin, Eli A. Stahl, Douglas Ruderfer, Maria Grigoroiu-Serbanescu, Georgia Panagiotaropoulou, Stephan Ripke, Tim B. Bigdeli, Frederike Stein, Tina Meller, Susanne Meinert, Helena Pelin, Fabian Streit, Sergi Papiol, Mark J. Adams, Rolf Adolfsson, Kristina Adorjan, Ingrid Agartz, Sofie R. Aminoff, Heike Anderson-Schmidt, Ole A. Andreassen, Raffaella Ardau, Jean-Michel Aubry, Ceylan Balaban, Nicholas Bass, Bernhard T. Baune, Frank Bellivier, Antoni Benabarre, Susanne Bengesser, Wade H Berrettini, Marco P. Boks, Evelyn J. Bromet, Katharina Brosch, Monika Budde, William Byerley, Pablo Cervantes, Catina Chillotti, Sven Cichon, Scott R. Clark, Ashley L. Comes, Aiden Corvin, William Coryell, Nick Craddock, David W. Craig, Paul E. Croarkin, Cristiana Cruceanu, Piotr M. Czerski, Nina Dalkner, Udo Dannlowski, Franziska Degenhardt, Maria Del Zompo, J. Raymond DePaulo, Srdjan Djurovic, Howard J. Edenberg, Mariam Al Eissa, Torbjørn Elvsåshagen, Bruno Etain, Ayman H. Fanous, Frederike Fellendorf, Alessia Fiorentino, Andreas J. Forstner, Mark A. Frye, Janice M. Fullerton, Katrin Gade, Julie Garnham, Elliot Gershon, Michael Gill, Fernando S. Goes, Katherine Gordon-Smith, Paul Grof, Jose Guzman-Parra, Tim Hahn, Roland Hasler, Maria Heilbronner, Urs Heilbronner, Stephane Jamain, Esther Jimenez, Ian Jones, Lisa Jones, Lina Jonsson, Rene S. Kahn, John R. Kelsoe, James L. Kennedy, Tilo Kircher, George Kirov, Sarah Kittel-Schneider, Farah Klöhn-Saghatolislam, James A. Knowles, Thorsten M. Kranz, Trine Vik Lagerberg, Mikael Landen, William B. Lawson, Marion Leboyer, Qingqin S. Li, Mario Maj, Dolores Malaspina, Mirko Manchia, Fermin Mayoral, Susan L. McElroy, Melvin G. McInnis, Andrew M. McIntosh, Helena Medeiros, Ingrid Melle, Vihra Milanova, Philip B. Mitchell, Palmiero Monteleone, Alessio Maria Monteleone, Markus M. Nöthen, Tomas Novak, John I. Nurnberger, Niamh O'Brien, Kevin S. O'Connell, Claire O'Donovan, Michael C. O'Donovan, Nils Opel, Abigail Ortiz, Michael J. Owen, Erik Pålsson, Carlos Pato, Michele T. Pato, Joanna Pawlak, Julia-Katharina Pfarr, Claudia Pisanu, James B. Potash, Mark H Rapaport, Daniela Reich-Erkelenz, Andreas Reif, Eva Reininghaus, Jonathan Repple, Hélène Richard-Lepouriel, Marcella Rietschel, Kai Ringwald, Gloria Roberts, Guy Rouleau, Sabrina Schaupp, William A Scheftner, Simon Schmitt, Peter R. Schofield, K. Oliver Schubert, Eva C. Schulte, Barbara Schweizer, Fanny Senner, Giovanni Severino, Sally Sharp, Claire Slaney, Olav B. Smeland, Janet L. Sobell, Alessio Squassina, Pavla Stopkova, John Strauss, Alfonso Tortorella, Gustavo Turecki, Joanna Twarowska-Hauser, Marin Veldic, Eduard Vieta, John B. Vincent, Wei Xu, Clement C. Zai, Peter P. Zandi, Psychiatric Genomics Consortium (PGC) Bipolar Disorder Working Group, International Consortium on Lithium Genetics (ConLiGen), Colombia-US Cross Disorder Collaboration in Psychiatric Genetics, Arianna Di Florio, Jordan W. Smoller, Joanna M. Biernacka, Francis J. McMahon, Martin Alda, Bertram Müller-Myhsok, Nikolaos Koutsouleris, Peter Falkai, Nelson B. Freimer, Till F.M. Andlauer, Thomas G. Schulze, Roel A. Ophoff
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- Journal:
- The British Journal of Psychiatry / Volume 219 / Issue 6 / December 2021
- Published online by Cambridge University Press:
- 25 August 2021, pp. 659-669
- Print publication:
- December 2021
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Background
Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.
AimsTo examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.
MethodGenome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.
ResultsEarlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.
ConclusionsAAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.
Coronavirus disease 2019 (COVID-19) research agenda for healthcare epidemiology
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- Lona Mody, Ibukunoluwa C. Akinboyo, Hilary M. Babcock, Werner E. Bischoff, Vincent Chi-Chung Cheng, Kathleen Chiotos, Kimberly C. Claeys, K. C. Coffey, Daniel J. Diekema, Curtis J. Donskey, Katherine D. Ellingson, Heather M. Gilmartin, Shruti K. Gohil, Anthony D. Harris, Sara C. Keller, Eili Y. Klein, Sarah L. Krein, Jennie H Kwon, Adam S. Lauring, Daniel J. Livorsi, Eric T. Lofgren, Katreena Merrill, Aaron M. Milstone, Elizabeth A. Monsees, Daniel J. Morgan, Luci P. Perri, Christopher D. Pfeiffer, Clare Rock, Sanjay Saint, Emily Sickbert-Bennett, Felicia Skelton, Katie J. Suda, Thomas R. Talbot, Valerie M. Vaughn, David J. Weber, Timothy L. Wiemken, Mohamed H. Yassin, Matthew J. Ziegler, Deverick J. Anderson
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 43 / Issue 2 / February 2022
- Published online by Cambridge University Press:
- 25 January 2021, pp. 156-166
- Print publication:
- February 2022
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This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to coronavirus disease 2019 (COVID-19) with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplementary materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
3177 Determining mechanisms underlying hippocampal network disruption in early amyloid pathology
- Adam Caccavano, P. Lorenzo Bozzelli, Katherine Conant, Stefano Vicini
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- Journal of Clinical and Translational Science / Volume 3 / Issue s1 / March 2019
- Published online by Cambridge University Press:
- 26 March 2019, pp. 103-104
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OBJECTIVES/SPECIFIC AIMS: Alzheimer’s disease (AD) is the leading cause of dementia, and a rapidly growing public health crisis as life expectancy increases. Two hallmark symptoms of the disease are memory impairment and the pathological accumulation of amyloid beta protein. The hippocampus is a brain region critical for the consolidation of new memories, and one of the first regions in which amyloid accumulation is observed. Our lab and others have observed a disruption to hippocampal network activity that is critical for memory consolidation in amyloid-accumulating mice. However, the mechanisms and neuronal micro-circuitry underlying this disruption are under-explored, a critical gap that warrants exploration if we are to understand memory disruption in the disease. In this study we have investigated the hypothesis that a preferential disruption to inhibitory PV neurons and the extracellular matrix that surrounds this cell type underlies downstream network alterations. METHODS/STUDY POPULATION: We have employed the 5xFAD mouse model of familial Alzheimer’s disease crossed with transgenic lines that selectively fluoresce in different neuronal sub-types. In a multi-modal approach, we have investigated behavioral, electrophysiological, and biochemical alterations between 3-month-old amyloid-accumulating 5xFAD mice and littermate controls. RESULTS/ANTICIPATED RESULTS: We observe a 35% increase in the incidence of synchronous hippocampal oscillations known as sharp wave ripples (SWRs) in amyloid-accumulating mice versus littermate controls (n = 28, p = 0.01), as well as a 95% increase in the power of slow gamma oscillations (p = 0.002). This hyperexcitability of the hippocampal network is correlated with an impairment in hippocampal-dependent memory, assayed with the Barnes Maze, a behavioral test of spatial memory (172% increase in latency to find escape hole, n = 8, p = 0.01). To elucidate the micro-circuitry that underlies this network disruption, we have investigated the integrity of peri-neuronal nets (PNNs), part of the extracellular matrix of proteins that preferentially ensheathe inhibitory PV neurons and support their function. We observe a 60% decrease in intensity of PNNs (n = 5, p = 0.005), suggesting PNN integrity is impaired in amyloid-accumulating mice. Ongoing experiments into the activity and synaptic input to both inhibitory PV and excitatory pyramidal neurons seek to determine the effects of this PNN disruption on downstream micro-circuitry. DISCUSSION/SIGNIFICANCE OF IMPACT: These findings suggest that a preferential impairment to PNNs and inhibitory PV cells underlie hippocampal hyperexcitability in a mouse model of AD. As hippocampal network activity is critical for memory consolidation, these effects contribute to our understanding of memory disruption during early disease progression, which has been poorly understood to date. These findings provide a foundation for future in vivo studies employing optogenetic stimulation to this neuronal sub-type, to determine if restoring physiological network balance can ameliorate memory decline.
The dwarf galaxy population as revealed by ALFALFA
- Elizabeth A. K. Adams, Catherine Ball, John M. Cannon, Martha P. Haynes, Alec Hirschauer, Riccardo Giovanelli, William Janesh, Steven Janowiecki, Luke Leisman, Kristen B. W. McQuinn, Katherine L. Rhode, John J. Salzer
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- Journal:
- Proceedings of the International Astronomical Union / Volume 14 / Issue S344 / August 2018
- Published online by Cambridge University Press:
- 30 October 2019, pp. 464-467
- Print publication:
- August 2018
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The combination of sensitivity and large sky coverage of the ALFALFA HI survey has enabled the detection of difficult to observe low mass galaxies in large numbers, including dwarf galaxies overlooked in optical surveys. Three different, but connected, studies of dwarf galaxies from the ALFALFA survey are of particular interest: SHIELD (Survey of HI in Extremely Low-mass Dwarfs), candidate gas-rich ultra-faint dwarf galaxies, and the (Almost) Dark population. SHIELD is a systematic multiwavelength study of all dwarf galaxies from ALFALFA with MHI < 107.2M⊙ and clear optical counterparts. Candidate gas-rich ultra-faint dwarf galaxies extend the dwarf galaxy population to even lower masses. These galaxies are identified as isolated HI clouds with no discernible optical counterpart but subsequent observations reveal that some are extremely faint, gas-dominated galaxies. Leo P, discovered first as an HI detection, and then found to be an actively star-forming galaxy, bridges the gap between these candidate galaxies and the SHIELD sample. The (Almost) Dark sample consists of galaxies whose optical counterparts are overlooked in current optical surveys but which are clear detections in ALFALFA. This sample includes field gas-rich ultra-diffuse galaxies. Coma P, with a peak surface brightness of only ∼26.4 mag arcsec−2 in g’, demonstrates the sort of extreme low surface brightness galaxy that can be discovered in an HI survey.
Dietary gap assessment: an approach for evaluating whether a country’s food supply can support healthy diets at the population level
- Edye M Kuyper, Reina Engle-Stone, Joanne E Arsenault, Mary Arimond, Katherine P Adams, Kathryn G Dewey
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- Journal:
- Public Health Nutrition / Volume 20 / Issue 13 / September 2017
- Published online by Cambridge University Press:
- 21 June 2017, pp. 2277-2288
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Objective
Dietary diversity, and in particular consumption of nutrient-rich foods including fruits, vegetables, nuts, beans and animal-source foods, is linked to greater nutrient adequacy. We developed a ‘dietary gap assessment’ to evaluate the degree to which a nation’s food supply could support healthy diets at the population level.
Design/SettingIn the absence of global food-based dietary guidelines, we selected the Dietary Approaches to Stop Hypertension (DASH) diet as an example because there is evidence it prevents diet-related chronic disease and supports adequate micronutrient intakes. We used the DASH guidelines to shape a hypothetical ‘healthy’ diet for the test country of Cameroon. Food availability was estimated using FAO Food Balance Sheet data on country-level food supply. For each of the seven food groups in the ‘healthy’ diet, we calculated the difference between the estimated national supply (in kcal, edible portion only) and the target amounts.
ResultsIn Cameroon, dairy and other animal-source foods were not adequately available to meet healthy diet recommendations: the deficit was −365 kcal (–1527 kJ)/capita per d for dairy products and −185 kcal (–774 kJ)/capita per d for meat, poultry, fish and eggs. Adequacy of fruits and vegetables depended on food group categorization. When tubers and plantains were categorized as vegetables and fruits, respectively, supply nearly met recommendations. Categorizing tubers and plantains as starchy staples resulted in pronounced supply shortfalls: −109 kcal (–457 kJ)/capita per d for fruits and −94 kcal (–393 kJ)/capita per d for vegetables.
ConclusionsThe dietary gap assessment illustrates an approach for better understanding how food supply patterns need to change to achieve healthier dietary patterns.
Contributors
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- Book:
- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
- Print publication:
- 27 April 2015, pp ix-xxx
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Contributors
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- By Naila A. Ahmad, Dua M. Anderson, Jennifer Aunspaugh, Sabrina T. Bent, Adam Broussard, Staci Cameron, Rahul Dasgupta, Ravinder Devgun, Ofer N. Eytan, Sean H. Flack, Terry G. Fletcher, Charles James Fox, Mary Elise Fox, Scott Friedman, Louise K. Furukawa, Sonja Gennuso, Stanley M. Hall, Hani Hanna, Jacob Hummel, James E. Hunt, Ranu Jain, Joe R. Jansen, Deepa Kattail, Alan David Kaye, David J. Krodel, Gregory J. Latham, Sungeun Lee, Michael G. Levitzky, Alexander Y. Lin, Carl Lo, Hoa N. Luu, Camila Lyon, Kelly A. Machovec, Lizabeth D. Martin, Maria Matuszczak, Patrick S. McCarty, Brenda C. McClain, J. Grant McFadyen, Helen Nazareth, Dolores B. Njoku, Christina M. Pabelick, Shannon M. Peters, Amit Prabhakar, Michael Richards, Kasia Rubin, Joel A. Saltzman, Lisgelia Santana, Gabriel Sarah, Katherine Stammen, John Stork, Kim M. Strupp, Lalitha V. Sundararaman, Rosalie F. Tassone, Douglas R. Thompson, Nicole C. P. Thompson, Paul A. Tripi, Jacqueline L. Tutiven, Navyugjit Virk, Stacey Watt, B. Craig Weldon, Maria Zestus
- Edited by Alan David Kaye, Louisiana State University, Charles James Fox, Tulane University School of Medicine, Louisiana, James H. Diaz, Louisiana State University
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- Book:
- Essentials of Pediatric Anesthesiology
- Published online:
- 05 November 2014
- Print publication:
- 16 October 2014, pp ix-xii
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NIH EXAMINER: Conceptualization and Development of an Executive Function Battery
- Joel H. Kramer, Dan Mungas, Katherine L. Possin, Katherine P. Rankin, Adam L. Boxer, Howard J. Rosen, Alan Bostrom, Lena Sinha, Ashley Berhel, Mary Widmeyer
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- Journal:
- Journal of the International Neuropsychological Society / Volume 20 / Issue 1 / January 2014
- Published online by Cambridge University Press:
- 08 October 2013, pp. 11-19
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Executive functioning is widely targeted when human cognition is assessed, but there is little consensus on how it should be operationalized and measured. Recognizing the difficulties associated with establishing standard operational definitions of executive functioning, the National Institute of Neurological Disorders and Stroke entered into a contract with the University of California-San Francisco to develop psychometrically robust executive measurement tools that would be accepted by the neurology clinical trials and clinical research communities. This effort, entitled Executive Abilities: Measures and Instruments for Neurobehavioral Evaluation and Research (EXAMINER), resulted in a series of tasks targeting working memory, inhibition, set shifting, fluency, insight, planning, social cognition and behavior. We describe battery conceptualization and development, data collection, scale construction based on item response theory, and lay the foundation for studying the battery's utility and validity for specific assessment and research goals. (JINS, 2013, 19, 1–9)
List of Contributors
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- By Adam K. Anderson, Jorge Armony, Anthony P. Atkinson, Sonia Bishop, Carolin Brück, Roberto Cabeza, Frances S. Chen, Hugo D. Critchley, Mauricio R. Delgado, Ricardo de Oliveira-Souza, Gregor Domes, Judith Domínguez-Borràs, Joseph E. Dunsmoor, Thomas Ethofer, Dominic S. Fareri, Lesley K. Fellows, Sophie Forster, Katherine Gardhouse, Nathalie George, Jay A. Gottfried, Jung Eun Han, Ahmad R. Hariri, Neil A. Harrison, Markus Heinrichs, Alisha C. Holland, Andreas Keil, Elizabeth A. Kensinger, Johanna Kissler, Olga Klimecki, Stefan Koelsch, Sylvia D. Kreibig, Benjamin Kreifelts, Robert Kumsta, Kevin S. LaBar, Eamon J. McCrory, Aprajita Mohanty, Jorge Moll, John P. O’Doherty, Leticia Oliveira, Mirtes Pereira, Luiz Pessoa, K. Luan Phan, Pierre Rainville, David Sander, Annett Schirmer, Catherine L. Sebastian, Tania Singer, Chandra Sekhar Sripada, Peggy L. St. Jacques, Essi Viding, Patrik Vuilleumier, Dirk Wildgruber, Amy Winecoff, Roland Zahn
- Edited by Jorge Armony, McGill University, Montréal, Patrik Vuilleumier, Université de Genève
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- Book:
- The Cambridge Handbook of Human Affective Neuroscience
- Published online:
- 05 February 2013
- Print publication:
- 21 January 2013, pp xi-xii
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Notes on Contributors
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- By John Dennis Anderson, William Blazek, Linda Costanzo Cahir, Sharon Kehl Califano, Donna Campbell, Helena Chance, Melanie Dawson, Linda De Roche, Anne-Marie Evans, Susan Goodman, Jennifer Haytock, Adam Jabbur, Katherine Joslin, Pamela Knights, Heidi M. Kunz, Jessica Schubert McCarthy, Bonnie Shannon McMullen, Cecilia Macheski, Maureen E. Montgomery, Elsa Nettels, Julie Olin-Ammentorp, Emily J. Orlando, Robin Peel, Melissa M. Pennell, Laura Rattray, Judith P. Saunders, Sharon Shaloo, Gail D. Sinclair, Carol J. Singley, Margaret Toth, Gary Totten, Linda Wagner-Martin
- Edited by Laura Rattray, University of Hull
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- Book:
- Edith Wharton in Context
- Published online:
- 05 November 2012
- Print publication:
- 08 October 2012, pp ix-xvi
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Dissolution of Synroc in Deionised Water at 150°C
- Katherine L. Smith, Michael Colella, Gordon J. Thorogood, Mark G. Blackford, Gregory R. Lumpkin, Kaye P. Hart, Kathryn Prince, Elaine Loi, Adam Jostsons
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- Journal:
- MRS Online Proceedings Library Archive / Volume 465 / 1996
- Published online by Cambridge University Press:
- 03 September 2012, 349
- Print publication:
- 1996
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Synroc containing 20 wt% simulated high level waste (HLW) was subjected to two sets of leach tests at 150°C where the leachant was and was not replaced during the test (replacement and non-replacement testing). The leachant was a KH-phthalate buffered solution (pH 4.2). Samples were characterised before and after leach testing using SEM, AEM and SIMS. Elemental concentrations in leachates were measured using ICP-MS. In concert with the findings of i) a dissolution study of perovskite in a flowing leachant and ii) a previous Synroc dissolution study (wherein Synroc containing 10 wt% simulated HLW was subjected to periodic replacement, leach testing in deionised water at 150°C), the results of this study show that when the leachant replacement frequency is varied from 7 d to the duration of the test, there is no effect on leach rate or leaching mechanisms.
Characterization and Leaching Behavior of Plutonium-Bearing Synroc-C
- Katherine L. Smith, Gregory R. Lumpkin, Mark G. Blackford, Michelle Hambley, R. Arthur Day, Kaye P. Hart, Adam Jostsons
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- Journal:
- MRS Online Proceedings Library Archive / Volume 465 / 1996
- Published online by Cambridge University Press:
- 03 September 2012, 1267
- Print publication:
- 1996
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Synroc-C containing 10wt% simulated PW-4b-D HLW including 0.62 wt% 239Pu was subjected to MCC-1 type leach tests at 70°C in deionised water, silicate and carbonate leachates for 53 d and deionised water for 2472 d. The normalised total (i.e. unfiltered leachate + vessel wall) Pu leach rates in deionised water, silicate and carbonate leachates for periods up to 53 d were found to be of the order of 10-5, 10-4 and 10-4 g m-2 d-1 respectively. After 2472 d, the differential, normalised, Pu leach rate in deionised water dropped to ∼5 × 10-6 (total) and ∼5 × 10-8 (solution - after filtration through a 1000NMW filter) g m-2 d-1. SEM and AEM were used to characterise our starting material and investigate the secondary phases on the surfaces of leached Synroc-C discs. Calculated and measured normalised Pu leach rates are compared and the partitioning of Pu between zirconolite and perovskite is discussed.