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We undertake a comprehensive investigation into the distribution of in situ stars within Milky Way-like galaxies, leveraging TNG50 simulations and comparing their predictions with data from the H3 survey. Our analysis reveals that 28% of galaxies demonstrate reasonable agreement with H3, while only 12% exhibit excellent alignment in their profiles, regardless of the specific spatial cut employed to define in situ stars. To uncover the underlying factors contributing to deviations between TNG50 and H3 distributions, we scrutinise correlation coefficients among internal drivers (e.g. virial radius, star formation rate [SFR]) and merger-related parameters (such as the effective mass-ratio, mean distance, average redshift, total number of mergers, average spin-ratio, and maximum spin alignment between merging galaxies). Notably, we identify significant correlations between deviations from observational data and key parameters such as the median slope of virial radius, mean SFR values, and the rate of SFR change across different redshift scans. Furthermore, positive correlations emerge between deviations from observational data and parameters related to galaxy mergers. We validate these correlations using the Random Forest Regression method. Our findings underscore the invaluable insights provided by the H3 survey in unravelling the cosmic history of galaxies akin to the Milky Way, thereby advancing our understanding of galactic evolution and shedding light on the formation and evolution of Milky Way-like galaxies in cosmological simulations.
Advances in medicine have led to an improvement in life expectancy, thus increasing the population of older individuals within the criminal justice system. This study investigates the determinants of risk formulation, care plan, and disposition among older adult forensic patients (OAFP) in Ontario, Canada.
Methods
This retrospective analysis utilized the Ontario Review Board database, focusing on 161 OAFP, aged 55 years and older. Hierarchical regression was used to analyze the relationship between changes in risk and six blocks of variables: sociodemographic characteristics (Block 1), circumstances during the index offense (Block 2), current clinical profile (Block 3), past psychiatric history and behavioral patterns (Block 4), criminal history and legal status (Block 5), and recent violent events (Block 6).
Results
The median age of patients was 61 years (IQR 58–67), with 83.4% being male. Schizophrenia was the most common diagnosis (68.3%), and 9.3% had neurocognitive disorders. The model with six blocks of factors explained 92% of the variability in risk change. Models 2 (blocks 1 and 2) and 4 (blocks 1–4) were statistically significant, explaining 34% (p = 0.010) and 22% (p = 0.018) of the variance in the change in risk of threat to public safety, respectively. OAFP with a significant risk to public safety were more likely to be inpatients and less likely intoxicated during their index offense.
Conclusion
Resources, policies, and a supervised model of care to curtail behavioral risks are relevant to the care of OAFP. Innovative risk management models for OAFP are indicated.
Objectives/Goals: Transmission-blocking vaccines hold promise for malaria elimination by reducing community transmission. But a major challenge that limits the development of efficacious vaccines is the vast parasite’s genetic diversity. This work aims to assess the genetic diversity of the Pfs25 vaccine candidate in complex infections across African countries. Methods/Study Population: We employed next-generation amplicon deep sequencing to identify nonsynonymous single nucleotide polymorphisms (SNPs) in 194 Plasmodium falciparum samples from four endemic African countries: Senegal, Tanzania, Ghana, and Burkina Faso. The individuals aged between 1 and 74 years, but most of them ranged from 1 to 19 years, and all presented symptomatic P. falciparum infection. The genome amplicon sequencing was analyzed using Geneious software and P. falciparum 3D7 as a reference. The SPNs were called with a minimum coverage of 500bp, and for this work, we used a very sensitive threshold of 1% variant frequency to determine the frequency of SNPs. The identified SNPs were threaded to the crystal structure of the Pfs25 protein, which allowed us to predict the impact of the novel SNP in the protein or antibody binding. Results/Anticipated Results: We identified 26 SNPs including 24 novel variants, and assessed their population prevalence and variant frequency in complex infections. Notably, five variants were detected in multiple samples (L63V, V143I, S39G, L63P, and E59G), while the remaining 21 were rare variants found in individual samples. Analysis of country-specific prevalence showed varying proportions of mutant alleles, with Ghana exhibiting the highest prevalence (44.6%), followed by Tanzania (12%), Senegal (11.8%), and Burkina Faso (2.7%). Moreover, we categorized SNPs based on their frequency, identifying dominant variants (>25%), and rare variants (Discussion/Significance of Impact: We identified additional SNPs in the Pfs25 gene beyond those previously reported. However, the majority of these newly discovered display low variant frequency and population prevalence. Further research exploring the functional implications of these variations will be important to elucidate their role in malaria transmission.
To examine the extent and nature of food and non-alcoholic drink advertising displayed on public transport and infrastructure on school routes.
Design:
Audit of outdoor advertisements on government-controlled public transport and associated infrastructure (e.g. tram shelters, bus stops) on busy school routes in Victoria, Australia. Using a strict protocol, trained field workers collected data on the type and content of outdoor advertising during February 2023 (start of school year). Food/drink advertising was classified (unhealthy or healthy) according to the Council of Australian Governments Health Council National interim guide to reduce children’s exposure to unhealthy food and drink promotion (2018).
Setting:
Government-controlled buses, trams and public transport infrastructure on routes from eleven of the busiest train stations in metropolitan Melbourne and regional Victoria, Australia to fifty public primary and secondary schools. Stations were chosen based on annual patronage, area-based socio-economic area (SEA) and regionality).
Results:
156 out of 888 advertisements were for food and non-alcoholic drinks. Of these, almost six in ten (58 %) were deemed unhealthy irrespective of SEA or regionality. Marketing appeals most featured were taste (31 %), convenience (28 %) and emotion (9 %). A significantly higher proportion of unhealthy advertisements were displayed within 500 m of schools v. outside this radius (91 % v. 57 %, P < 0·01).
Conclusion:
Given the detrimental impacts of exposure to unhealthy food/drink advertising on children’s diets, the pervasive, powerful presence of such advertising across government public transport assets, particularly around schools, contradicts public health recommendations to protect children from exposure to and influence by this harmful marketing and warrants government action.
To assess the impact of a diagnostic test stewardship intervention focused on tracheal aspirate cultures.
Design:
Quality improvement intervention.
Setting:
Tertiary care pediatric intensive care unit (PICU).
Patients:
Mechanically ventilated children admitted between 9/2018 and 8/2022.
Methods:
We developed and implemented a consensus guideline for obtaining tracheal aspirate cultures through a series of Plan-Do-Study-Act cycles. Change in culture rates and broad-spectrum antibiotic days of therapy (DOT) per 100 ventilator days were analyzed using statistical process control charts. A secondary analysis comparing the preintervention baseline (9/2018–8/2020) to the postintervention period (9/2020–8/2021) was performed using Poisson regression.
Results:
The monthly tracheal aspirate culture rate prior to the COVID-19 pandemic (9/2018–3/2020) was 4.6 per 100 ventilator days. A centerline shift to 3.1 cultures per 100 ventilator days occurred in 4/2020, followed by a second shift to 2.0 cultures per 100 ventilator days in 12/2020 after guideline implementation. In our secondary analysis, the monthly tracheal aspirate culture rate decreased from 4.3 cultures preintervention (9/2018–8/2020) to 2.3 cultures per 100 ventilator days postintervention (9/2020–8/2021) (IRR 0.52, 95% CI 0.47–0.59, P < 0.01). Decreases in tracheal aspirate culture use were driven by decreases in inappropriate cultures. Treatment of ventilator-associated infections decreased from 1.0 to 0.7 antibiotic courses per 100 ventilator days (P = 0.03). There was no increase in mortality, length of stay, readmissions, or ventilator-associated pneumonia postintervention.
Conclusion:
A diagnostic test stewardship intervention was both safe and effective in reducing the rate of tracheal aspirate cultures and treatment of ventilator-associated infections in a tertiary PICU.
Children’s peer victimization trajectories and their longitudinal associations with externalizing and internalizing problems were investigated from Grades 2 to 5. Secondary data analysis was performed with the Early Childhood Longitudinal Study (ECLS-K-2011; n = 13,860, Mage = 8.1 years old in the spring of Grade 2; 51.1% male, 46.7% White, 13.2% African-American, 25.3% Hispanic or Latino, 8.5% Asian, and 6.1% other or biracial). Children who experienced high and persistent levels of peer victimization (high-chronic victims) exhibited co-occurring externalizing and internalizing problems. Moreover, among high-chronic victims, boys had a more pronounced increase in their externalizing trajectories, and girls had greater increases in their social anxiety trajectories. In contrast, those with decreasing peer victimization across time exhibited signs of recovery, particularly with respect to their social anxiety. These findings elucidated how chronic, increasing, and decreasing victims exhibited distinct patterns in the co-occurring development of their externalizing and internalizing problems, and how findings varied depending on the form of problem behavior and by child sex.
To examine the association between adherence to plant-based diets and mortality.
Design:
Prospective study. We calculated a plant-based diet index (PDI) by assigning positive scores to plant foods and reverse scores to animal foods. We also created a healthful PDI (hPDI) and an unhealthful PDI (uPDI) by further separating the healthy plant foods from less-healthy plant foods.
Setting:
The VA Million Veteran Program.
Participants:
315 919 men and women aged 19–104 years who completed a FFQ at the baseline.
Results:
We documented 31 136 deaths during the follow-up. A higher PDI was significantly associated with lower total mortality (hazard ratio (HR) comparing extreme deciles = 0·75, 95 % CI: 0·71, 0·79, Ptrend < 0·001]. We observed an inverse association between hPDI and total mortality (HR comparing extreme deciles = 0·64, 95 % CI: 0·61, 0·68, Ptrend < 0·001), whereas uPDI was positively associated with total mortality (HR comparing extreme deciles = 1·41, 95 % CI: 1·33, 1·49, Ptrend < 0·001). Similar significant associations of PDI, hPDI and uPDI were also observed for CVD and cancer mortality. The associations between the PDI and total mortality were consistent among African and European American participants, and participants free from CVD and cancer and those who were diagnosed with major chronic disease at baseline.
Conclusions:
A greater adherence to a plant-based diet was associated with substantially lower total mortality in this large population of veterans. These findings support recommending plant-rich dietary patterns for the prevention of major chronic diseases.
China’s Belt and Road Initiative (BRI), designed to build critical infrastructure and coordinate economic growth, is the most significant development initiative in modern history. The BRI has a documented vision for sustainability, including environmental impact assessments and responsibility tenets. Despite this, a growing body of literature has found adverse effects of BRI projects on protected land and species. To understand corporate responsibility and regulations for companies participating in the BRI, we gathered information on 260 BRI companies using the Refinitiv Eikon BRI Connect database and the China Global Investment Tracker. The results revealed a significant gap in corporate responsibility reporting for biodiversity impacts, environmental restoration, environmental project financing and the United Nations’ Sustainable Development Goals (SDG) 14 ‘Life below Water’ and 15 ‘Life on Land’. The modest fraction of companies that we found to report biodiversity accountability highlights the need to restructure and incentivize the reporting of environmental and biodiversity risks. The current evidence of limited adherence to responsibility measures highlights a clear opportunity to align BRI development with the BRI’s vision for sustainability, and to strengthen links for policy engagement within Chinese regulatory frameworks and international obligations at the United Nations within its SDG framework.
Intracranial hemorrhage after endovascular thrombectomy is associated with poorer prognosis compared with those who do not develop the complication. Our study aims to determine predictors of post-EVT hemorrhage – more specifically, inflammatory biomarkers present in baseline serology.
Methods:
We performed a retrospective review of consecutive patients treated with EVT for acute large vessel ischemic stroke. The primary outcome of the study is the presence of ICH on the post-EVT scan. We used four definitions: the SITS-MOST criteria, the NINDS criteria, asymptomatic hemorrhage, and overall hemorrhage. We identified nonredundant predictors of outcome using backward elimination based on Akaike Information Criteria. We then assessed prediction accuracy using area under the receiver operating curve. Then we implemented variable importance ranking from logistic regression models using the drop in Naegelkerke R2 with the exclusion of each predictor.
Results:
Our study demonstrates a 6.3% SITS (16/252) and 10.0% NINDS (25/252) sICH rate, as well as a 19.4% asymptomatic (49/252) and 29.4% (74/252) overall hemorrhage rate. Serologic markers that demonstrated association with post-EVT hemorrhage were: low lymphocyte count (SITS), high neutrophil count (NINDS, overall hemorrhage), low platelet to lymphocyte ratio (NINDS), and low total WBC (NINDS, asymptomatic hemorrhage).
Conclusion:
Higher neutrophil counts, low WBC counts, low lymphocyte counts, and low platelet to lymphoycyte ratio were baseline serology biomarkers that were associated with post-EVT hemorrhage. Our findings, particularly the association of diabetes mellitus and high neutrophil, support experimental data on the role of thromboinflammation in hemorrhagic transformation of large vessel occlusions.
Background: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a frequent cause of healthcare-associated infections (HAIs). The CDC Emerging Infections Program (EIP) conducted population and laboratory-based surveillance of CRPA in selected areas in 8 states from August 1, 2016, through July 31, 2018. We aimed to describe the molecular epidemiology and mechanisms of resistance of CRPA isolates collected through this surveillance. Methods: We defined a case as the first isolate of P. aeruginosa resistant to imipenem, meropenem, or doripenem from the lower respiratory tract, urine, wounds, or normally sterile sites identified from a resident of the EIP catchment area in a 30-day period; EIP sites submitted a systematic random sample of isolates to CDC for further characterization. Of 1,021 CRPA clinical isolates submitted, 707 have been sequenced to date using an Illumina MiSeq. Sequenced genomes were classified using the 7-gene multilocus sequence typing (MLST) scheme, and a core genome MLST (cgMLST) scheme was used to determine phylogeny. Antimicrobial resistance genes were identified using publicly available databases, and chromosomal mechanisms of carbapenem resistance were determined using previously validated genetic markers. Results: There were 189 sequence types (STs) among the 707 sequenced genomes (Fig. 1). The most frequently occurring were high-risk clones ST235 (8.5%) and ST298 (4.7%), which were found across all EIP sites. Carbapenemase genes were identified in 5 (<1%) isolates. Overall, 95.6% of the isolates had chromosomal mutations associated with carbapenem resistance: 93.2% had porinD-associated mutations that decrease membrane permeability to the drugs; 24.8% had mutations associated with overexpression of the multidrug efflux pump MexAB-OprM; and 22.9% had mutations associated with overexpression of the endogenous β-lactamase ampC. More than 1 such chromosomal resistance mutation type was present in 37.8% of the isolates. Conclusions: The diversity of the sequence types demonstrates that HAIs caused by CRPA can arise from a variety of strains and that high-risk clones are broadly disseminated across the EIP sites but are a minority of CRPA strains overall. Carbapenem resistance in P. aeruginosa was predominantly driven by chromosomal mutations rather than acquired mechanisms (ie, carbapenemases). The diversity of the CRPA isolates and the lack of carbapenemase genes suggest that this ubiquitous pathogen can readily evolve chromosomal resistance mechanisms, but unlike carbapenemases, these cannot be easily spread through horizontal transfer.
Acute change in mental status (ACMS), defined by the Confusion Assessment Method, is used to identify infections in nursing home residents. A medical record review revealed that none of 15,276 residents had an ACMS documented. Using the revised McGeer criteria with a possible ACMS definition, we identified 296 residents and 21 additional infections. The use of a possible ACMS definition should be considered for retrospective nursing home infection surveillance.
To determine whether there were changes in the prevalence or healthiness of products carrying claims post-implementation of Standard 1.2.7: Nutrition, Health and Related Claims in the Australia New Zealand Food Standards Code.
Design:
Observational survey of claims on food packages in three categories: non-alcoholic beverages, breakfast cereals and cereal bars. Nutrient profiling was applied to products to determine their eligibility to carry health claims under Standard 1.2.7. The Standard came into effect in 2013. The proportion of products carrying claims and the proportion of those not meeting the nutrient profiling criteria were calculated. A comparative analysis was conducted to determine changes between 2011 and 2016.
Setting:
Three large metropolitan stores from the three major supermarket chains in Sydney, Australia were surveyed in 2011 and 2016.
Participants:
All claims on all available products in 2016 (n 1737). Nutrition composition and ingredients were collected from the packaging.
Results:
Overall in 2016, 76 % of products carried claims and there were 7367 claims identified in the three food categories. Of products in 2016 with health claims, 34 % did not meet nutrient profiling criteria. These may breach Standard 1.2.7. Comparison of 2011–2016 showed a significant increase in the number of products carrying claims (66 v. 76 %, P < 0·001).
Conclusions:
The proportion of products carrying claims that do not meet nutrient profiling and consumers’ tendency to infer health benefits from nutrition content claims warrants the regulation of all claims using the nutrient profiling. This will ensure consumers are not misled by claims on unhealthy food products.
Codex published the ‘Guidelines for Risk Analysis of Foodborne Antimicrobial Resistance’ to standardise the approach for evaluating risk posed by foodborne antimicrobial-resistant bacteria. One of the first steps in the guidelines is to compile a risk profile, which provides the current state of knowledge regarding a food safety issue, describes risk management options and recommends next steps. In Canada, ceftiofur/ceftriaxone-resistant Salmonella enterica subsp. enterica serovar Heidelberg from poultry was identified as an antimicrobial resistance (AMR) food safety issue. The first objective of this article was to contextualise this food safety issue, using the risk profile format of the Codex Guidelines. A second objective was to evaluate the applicability of the Codex Guidelines. This risk profile indicated that ceftiofur/ceftriaxone-resistant S. Heidelberg (CSH) was commonly isolated from poultry and was associated with severe disease in humans. Ceftiofur use in poultry hatcheries temporally mirrored the prevalence of CSH from poultry meat at retail and from people with salmonellosis. The evidence was sufficient to indicate the need for risk management options, such as restricting the use of ceftiofur in poultry. The Codex Guidelines provided a useful approach to summarise data for decision-makers to evaluate an AMR food safety issue.
Ethnic minority groups often have more complex and aversive pathways to mental health care. However, large population-based studies are lacking, particularly regarding involuntary hospitalisation. We sought to examine the risk of involuntary admission among first-generation ethnic minority groups with early psychosis in Ontario, Canada.
Methods
Using health administrative data, we constructed a retrospective cohort (2009–2013) of people with first-onset non-affective psychotic disorder aged 16–35 years. This cohort was linked to immigration data to ascertain migrant status and country of birth. We identified the first involuntary admission within 2 years and compared the risk of involuntary admission for first-generation migrant groups to the general population. To control for the role of migrant status, we restricted the sample to first-generation migrants and examined differences by country of birth, comparing risk of involuntary admission among ethnic minority groups to a European reference. We further explored the role of migrant class by adjusting for immigrant vs refugee status within the migrant cohort. We also explored effect modification of migrant class by ethnic minority group.
Results
We identified 15 844 incident cases of psychotic disorder, of whom 19% (n=3049) were first-generation migrants. Risk of involuntary admission was higher than the general population in five of seven ethnic minority groups. African and Caribbean migrants had the highest risk of involuntary admission (African: risk ratio (RR) = 1.52, 95% CI = 1.34–1.73; Caribbean: RR = 1.58, 95% CI = 1.37–1.82), and were the only groups where the elevated risk persisted when compared to the European reference group within the migrant cohort (African: RR=1.24, 95% CI = 1.04–1.48; Caribbean: RR=1.29, 95% CI = 1.07–1.56). Refugee status was independently associated with involuntary admission (RR=1.16, 95% CI = 1.02–1.32); however, this risk varied by ethnic minority group, with Caribbean refugees having an elevated risk of involuntary admission compared with Caribbean immigrants (RR=1.72, 95% CI = 1.15–2.58).
Conclusions
Our findings are consistent with the international literature showing increased rates of involuntary admission among some ethnic minority groups with early psychosis. Interventions aimed at improving pathways to care could be targeted at these groups to reduce disparities.
Although data sharing platforms host diverse data types the features of these platforms are well-suited to facilitating biomarker research. Given the current state of biomarker discovery, an innovative paradigm to accelerate biomarker discovery is to utilize platforms such as Vivli to leverage researchers' abilities to integrate certain classes of biomarkers.
Geomorphic evidence of past glaciation, such as U-shaped valleys, aretes, glacial lakes, and moraines, is preserved in the highland surrounding Cerro Chirripó in the Cordillera de Talamanca, Costa Rica. Previous work to establish a glacial chronology has focused on relative age dating of moraines and on radiocarbon dating of basal lake sediments to infer the timing of deglaciation. We used cosmogenic 36Cl surface exposure dating to constrain the ages of moraines within two formerly glaciated valleys, the Morrenas and Talari valleys. Forty-nine boulder samples were processed and measured from four moraine complexes in the Morrenas Valley and two moraine complexes in the Talari Valley. The exposure ages of these samples indicate a major glacial event occurred in this area from ~25 to 23 ka, broadly synchronous with the global last glacial maximum. Our results also indicate periods of glacial retreats and standstills from the deglacial period to the Early Holocene (~16–10 ka) before the complete disappearance of glaciers in this highland. These findings provide important insights into the glacial chronology and paleoclimate of tropical America.
To assess the extent of error present in self-reported weight data in the Women’s Health Initiative, variables that may be associated with error, and to develop methods to reduce any identified error.
Design
Prospective cohort study.
Setting
Forty clinical centres in the USA.
Participants
Women (n 75 336) participating in the Women’s Health Initiative Observational Study (WHI-OS) and women (n 6236) participating in the WHI Long Life Study (LLS) with self-reported and measured weight collected about 20 years later (2013–2014).
Results
The correlation between self-reported and measured weights was 0·97. On average, women under-reported their weight by about 2 lb (0·91 kg). The discrepancies varied by age, race/ethnicity, education and BMI. Compared with normal-weight women, underweight women over-reported their weight by 3·86 lb (1·75 kg) and obese women under-reported their weight by 4·18 lb (1·90 kg) on average. The higher the degree of excess weight, the greater the under-reporting of weight. Adjusting self-reported weight for an individual’s age, race/ethnicity and education yielded an identical average weight to that measured.
Conclusions
Correlations between self-reported and measured weights in the WHI are high. Discrepancies varied by different sociodemographic characteristics, especially an individual’s BMI. Correction of self-reported weight for individual characteristics could improve the accuracy of assessment of obesity status in postmenopausal women.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Previously, it has been suggested that metal ions complexed to humic acid in the environment might show slower dissociation than those added to humic substances in the laboratory, which has serious implications for the transport of radionuclides in the environment. The dissociationof lanthanide and anthropogenic actinide ions from humic substance complexes has been studied as a function of humic concentration and metal ion:humic concentration ratio. The results suggest that the apparently slower kinetics observed for metal ions complexed in the environment are probablydue to the large humic concentrations that are used in those studies. Further, there is no evidence that the dissociation rate constant varies at very low metal ion concentrations. Although humic samples size-fractionated by ultrafiltration showed that more metal may be bound non-exchangeably,there was no evidence for different rate constants. Ultrafiltration of Eu(III)/humic acid mixtures did show a shift in Eu from smaller to larger fractions over a period of two days. Therefore, the results suggest that dissociation rate constants determined in the laboratory at metal ion concentrationshigher than those expected in the environment may be used in predicting radionuclide mobility, provided that the humic acid concentration is in the range expected at the site.