Laboratory-Controlled Experiments Reveal Microbial Community Shifts during Sediment Resuspension Events.

In freshwater ecosystems, dynamic hydraulic events (floods or dam maintenance) lead to sediment resuspension and mixing with waters of different composition. Microbial communities living in the sediments play a major role in these leaching events, contributing to organic matter degradation and the release of trace elements. However, the dynamics of community diversity are seldom studied in the context of ecological studies. Therefore, we carried out laboratory-induced leaching experiments, using sediments from the Villerest dam reservoir (Villerest, France). To assess whole microbial community diversity, we sequenced the archaeal and bacterial 16S rRNA genes using Illumina MiSeq. Our results suggest that the degree of dissolved oxygen found in the water during these resuspension episodes influenced community dynamics, with anoxic waters leading to drastic shifts in sedimentary communities compared to oxic waters. Furthermore, the release of microbial cells from sediments to the water column were more favorable to water colonization when events were caused by oxic waters. Most of the bacteria found in the sediments were chemoorganotrophs and most of the archaea were methanogens. Methylotrophic, as well as archaeal, and bacterial chemoorganotrophs were detected in the leachate samples. These results also show that organic matter degradation occurred, likely participating in carbonate dissolution and the release of trace elements during freshwater resuspension events.

Behavioral Health Integration in Community Health Centers and Emergency Department Use.

Medicaid enrollees with behavioral health disorders often experience fragmented care, leading to high rates of preventable use of emergency departments (EDs). As part of its Medicaid Transformation Program, the Washington Health Care Authority partnered with regional accountable communities of health to collect data on behavioral health integration in community health centers. Clinics who participated in the integrated care demonstration received technical and financial support to increase capacity for integration. This column describes results from an analysis that linked clinic surveys to Medicaid claims to explore characteristics of highly integrated clinics and assess whether clinic capacity for behavioral health integration is associated with ED visit frequency.