Solution-borne colloids from drip tests using actinide-doped and fully-radioactive waste glasses

Drip tests designed to replicate the synergistic interactions between waste glass, repository groundwater, water vapor, and sensitized 304L stainless steel in the potential Yucca Mountain Repository have been ongoing in our laboratory for over ten years. Results will be presented from three sets of these drip tests: two with actinide-doped glasses, and one with a fully-radioactive glass. Periodic sampling of these tests have revealed trends in actinide release behavior that are consistent with their entrainment in colloidal material when as-cast glass is reacted. Results from vapor hydrated glass show that initially the actinides are completely dissolved in solution, but as the reaction proceeds, the actinides become suspended in solution. Sequential filtering and alpha spectroscopy of colloid-bearing leachate solutions indicate that more than 80 percent of the plutonium and americium are bound to particles that are captured by a 0. 1 gm filter, while less than 10 percent of the neptunium is stopped by a 0. 1 gm filter. Analytical transmission electron microscopy has been used to examine particles from leachate solutions and to identify several actinide-bearing phases which are responsible for the majority of actinide release during glass corrosion

An Evaluation of Glass-Crystal Composites For the Disposal of Nuclear and Hazardous Waste Materials

Waste forms made of a glass-crystal composite (GCC) are being evaluated at Argonne National Laboratory for their potential use in the disposal of low-level nuclear and hazardous waste materials. This waste form is being developed within the framework strategy of DOE`s minimum Additive Waste Stabilization (MAWS) Program. The MAWS protocol involves the blending of multiple waste streams to achieve an optimal feed composition, which eliminates the need to use large amounts of additives to produce an acceptable waste form. The GCCs have a particularly useful utility in their ability to incorporate waste streams with high metal contents, including those that contain large amounts of scrap metals, and in their potential for sequestering radionuclide and hazardous constituents in corrosion-resistant mineral phases. This paper reports the results from tests conducted with simulated feeds representative of potential DOE and industry waste streams. Topics addressed include the partitioning of various radioactive and hazardous constituents between the glass and crystalline portions of the waste form, the development of secondary phases on the altered sample surfaces during corrosion testing, and the fate of waste components during corrosion testing, as indicated by elements released to solution and microanalysis of the reacted solid samples

Practitioner Review: Therapist variability, patient-reported therapeutic alliance, and clinical outcomes in adolescents undergoing mental health treatment - a systematic review and meta-analysis

Background: Previous meta-analyses have only found small correlations (r=0.10 to r=0.19) between therapeutic alliance and clinical outcomes in samples of adolescents receiving psychological therapy. Although study-level variables have been found to moderate this, little is known about the impact of therapist variability. The present meta-analysis aimed to address this gap by using patient-therapist ratio as a moderator variable. Methods: Contrary to previous reviews of adolescent alliance, individual effect sizes were extracted using a pre-registered conceptual hierarchy. Controlling for treatment-level confounds, a random effects meta-analysis assessed the moderating effect of patient-therapist ratio on the alliance-outcome relationship in pre-defined single-predictor and multi-predictor meta-regressions.Results: The alliance-outcome relationship was found to be larger than previously thought (k=28, N=2911, r=0.29, 95% Confidence Interval 0.21, 0.37;

The genetic architecture of type 2 diabetes

The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of heritability. To test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole genome sequencing in 2,657 Europeans with and without diabetes, and exome sequencing in a total of 12,940 subjects from five ancestral groups. To increase statistical power, we expanded sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support a major role for lower-frequency variants in predisposition to type 2 diabetes

COVID-19: Rapid antigen detection for SARS-CoV-2 by lateral flow assay: A national systematic evaluation of sensitivity and specificity for mass-testing

Background Lateral flow device (LFD) viral antigen immunoassays have been developed around the world as diagnostic tests for SARS-CoV-2 infection. They have been proposed to deliver an infrastructure-light, cost-economical solution giving results within half an hour. Methods LFDs were initially reviewed by a Department of Health and Social Care team, part of the UK government, from which 64 were selected for further evaluation from 1st August to 15th December 2020. Standardised laboratory evaluations, and for those that met the published criteria, field testing in the Falcon-C19 research study and UK pilots were performed (UK COVID-19 testing centres, hospital, schools, armed forces). Findings 4/64 LFDs so far have desirable performance characteristics (orient Gene, Deepblue, Abbott and Innova SARS-CoV-2 Antigen Rapid Qualitative Test). All these LFDs have a viral antigen detection of >90% at 100,000 RNA copies/ml. 8951 Innova LFD tests were performed with a kit failure rate of 5.6% (502/8951, 95% CI: 5.1–6.1), false positive rate of 0.32% (22/6954, 95% CI: 0.20–0.48). Viral antigen detection/sensitivity across the sampling cohort when performed by laboratory scientists was 78.8% (156/198, 95% CI 72.4–84.3). Interpretation Our results suggest LFDs have promising performance characteristics for mass population testing and can be used to identify infectious positive individuals. The Innova LFD shows good viral antigen detection/sensitivity with excellent specificity, although kit failure rates and the impact of training are potential issues. These results support the expanded evaluation of LFDs, and assessment of greater access to testing on COVID-19 transmission. Funding Department of Health and Social Care. University of Oxford. Public Health England Porton Down, Manchester University NHS Foundation Trust, National Institute of Health Research

Disposition of Actinides Released From High-Level Waste Glass

A series of static leach tests was conducted using glasses developed for vitrifying tank wastes at the Savannah River Site to monitor the disposition of actinide elements upon corrosion of the glasses. In these tests, glasses produced from SRL 131 and SRL 202 frits were corroded at 90{degrees}C in a tuff groundwater. Tests were conducted using crushed glass at different glass surface area-to-solution volume (S/V) ratios to assess the effect of the S/V on the solution chemistry, the corrosion of the glass, and the disposition of actinide elements. Observations regarding the effects of the S/V on the solution chemistry and the corrosion of the glass matrix have been reported previously. This paper highlights the solution analyses performed to assess how the S/V used in a static leach test affects the disposition of actinide elements between fractions that are suspended or dissolved in the solution, and retained by the altered glass or other materials

Cortisol concentrations in blood and urine of horses

A survey of the concentrations of cortisol in blood and urine samples taken from thoroughbred and standardbred horses after racing is presented. Statistical analysis showed the only significant difference between thoroughbred and standardbred horses was a higher cortisol concentration in thoroughbred urine. Urine volume and pH had no significant influence on the urinary cortisol concentration, however 9.5% of the urinary cortisol variation could be explained due to the influence of plasma cortisol concentration. The results of cortisol and ACTH administrations are also shown and compared with the survey results

Laboratory testing of glasses for Lockheed Idaho Technology Company: Final report

Tests have been conducted at Argonne National Laboratory (ANL) in support of the efforts of Lockheed Idaho Technology Company (LITCO) to vitrify high-level waste calcines. Tests were conducted with three classes of LITCO glass formulations: Formula 127 (fluorine-bearing), Formula 532 (fluorine-free), and 630 series (both single- and mixed-alkali) glasses. The test matrices included, as appropriate, the Product Consistency Test Method B (PCT-B), the Materials Characterization Center Test 1 (MCC-1), and the Argonne vapor hydration test (VHT). Test durations ranged from 7 to 183 d. In 7-d PCT-Bs, normalized mass losses of major glass-forming elements for the LITCO glasses are similar to, or lower than, normalized mass losses obtained for other domestic candidate waste glasses. Formula 532 glasses form zeolite alteration phases relatively early in their reaction with water. The formation of those phases increased the dissolution rate. In contrast, the Formula 127 glass is highly durable and forms alteration phases only after prolonged exposure to water in tests with very high surface area to volume ratios; these alteration phases have a relatively small effect on the rate of glass corrosion. No alteration phases formed within the maximum test duration of 183 d in PCT-Bs with the 630 series glasses. The corrosion behavior of the mixed-alkali 630 series glasses is similar to that of 630 series glasses containing sodium alone. In VHTs, both single- and mixed-alkali glasses form zeolite phases that increase the rate of glass reaction. The original 630 series glasses and those based on a revised surrogate calcine formulation react at the same rate in PCT-Bs and form the same major alteration phases in VHTs