PFAS in biosolids: Accumulation characteristics and fate profiles after land application.

The land application of biosolids as a management practice is considered a beneficial use for improving crop yield and reducing the need for other fertilizers. PFAS enter wastewater treatment plants through collection networks, including industrial discharges, the use of PFAS-containing products, and runoff. Therefore, PFAS may be present in biosolids derived from sewage sludge. The objectives of this study were to evaluate PFAS levels in biosolids samples collected at two wastewater treatment plants operated by the Miami Dade Water and Sewer Department (MDWASD): (1) the South District Wastewater Treatment Plant (SDWWTP) which received landfill leachate and (2) the Central District Wastewater Treatment Plant (CDWWTP). Sludge samples were collected after thickening, anaerobic digestion, and dewatering processes. The samples were subjected to batch leaching tests for 30 days. After the leaching tests, the PFAS levels in the liquid and solid fractions were analyzed for 40 PFAS. The findings show that during the aeration process (i.e., activated sludge process), PFAS are removed from the wastewater and accumulate on the solids. When the thickened sludge is digested, some PFAS are released to the liquid phase as the volatile solids decompose. During the dewatering process by centrifugation, PFAS that are partitioned to the liquid phase are removed, reducing PFAS content in the dewatered biosolids. Of the 40 PFAS analyzed, 24 were detected in leachate or solid residue samples. Samples from the SDWWTP had higher levels of PFAS due to the contribution from landfill leachate discharged to this facility. The partitioning of PFAS between the liquid phase and solid residue after 30 days of mixing indicates that the majority of PFAS in the biosolids are highly soluble and have a high tendency to be mobilized (by runoff, irrigation, precipitation) after land application. The fate profiles of PFAS biosolids were evaluated in terms of their solubility and retardation characteristics.

Design and Implementation of a Skilled Nursing Facility COVID-19 Unit.

Coronavirus disease 2019 (COVID-19) has challenged the health care system's capacity to care for acutely ill patients. In a collaborative partnership between a health system and a skilled nursing facility (SNF), we developed and implemented an SNF COVID-19 unit to allow expedited hospital discharge of COVID-positive older adults who are clinically improving, and to provide an alternative to hospitalization for those who require SNF care but do not require or necessarily desire aggressive disease-modifying interventions.

A haemagglutination test for rapid detection of antibodies to SARS-CoV-2

Serological detection of antibodies to SARS-CoV-2 is essential for establishing rates of seroconversion in populations, detection of seroconversion after vaccination, and for seeking evidence for a level of antibody that may be protective against COVID-19 disease. Several high-performance commercial tests have been described, but these require centralised laboratory facilities that are comparatively expensive, and therefore not available universally. Red cell agglutination tests have a long history in blood typing, and general serology through linkage of reporter molecules to the red cell surface. They do not require special equipment, are read by eye, have short development times, low cost and can be applied as a Point of Care Test (POCT). We describe a red cell agglutination test for the detection of antibodies to the SARS-CoV-2 receptor binding domain (RBD). We show that the Haemagglutination Test ("HAT") has a sensitivity of 90% and specificity of 99% for detection of antibodies after a PCR diagnosed infection. The HAT can be titrated, detects rising titres in the first five days of hospital admission, correlates well with a commercial test that detects antibodies to the RBD, and can be applied as a point of care test. The developing reagent is composed of a previously described nanobody to a conserved glycophorin A epitope on red cells, linked to the RBD from SARS-CoV-2. It can be lyophilised for ease of shipping. We have scaled up production of this reagent to one gram, which is sufficient for ten million tests, at a cost of [~]0.27 UK pence per test well. Aliquots of this reagent are ready to be supplied to qualified groups anywhere in the world that need to detect antibodies to SARS-CoV-2, but do not have the facilities for high throughput commercial tests.

White matter damage in maintenance hemodialysis patients: a diffusion tensor imaging study.

BACKGROUND: Patients treated with dialysis have high rates of brain infarcts, brain atrophy, and white matter disease. There are limited data regarding the presence of more subtle damage to brain white matter. METHODS: In the Cognition and Dialysis Study, we compared brain structure using diffusion tensor imaging in hemodialysis (HD) patients to individuals without known kidney disease, using tract based spatial statistics (TBSS) to compare Fractional Anisotropy (FA) and Mean Diffusivity (MD). Statistical comparison of each overlaid voxel was age controlled using a permutation based corrected p value of <0.05. RESULTS: Thirty-four HD patients and twenty six controls (52 vs 51 years for HD vs control) had adequate magnetic resonance imaging for analysis. The HD group had fewer women (38% vs 23%) and a higher prevalence of diabetes (29% vs 8%), heart failure (29% vs 0%) and clinical stroke (15% vs 0%). Hemodialysis patients had significantly lower FA across multiple white matter fiber tracts, with fronto-temporal connections, the genu of the corpus callosum and the fornix more significantly affected than posterior regions of the brain. Similarly, HD patients had significantly higher mean diffusivity in multiple anterior brain regions. Results remained similar when those with a prior history of stroke were excluded. CONCLUSIONS: In HD patients, there is more white matter disease in the anterior than posterior parts of the brain compared to controls without kidney disease. This pattern of injury is most similar to that seen in aging, suggesting that developing chronic kidney disease and ultimately kidney failure may result in a phenotype consistent with accelerated aging.