Effect of Terminal Electron Accepting Processes on Acetate Thresholds in Contaminated Sediments

Demonstrating the success of in situ bioremediation is challenging, requiring multiple lines of evidence, e.g., "footprints" of microbially-mediated processes that transform contaminants, like metabolic intermediates. This project evaluated the hypothesis that characteristic threshold concentrations of acetate, a key intermediate under anaerobic conditions, occur in contaminant plume regions dominated by different terminal electron accepting processes (TEAPs). The evaluation included characterizing the initially predominant TEAP(s) in sediment-slurry microcosms, and then measuring acetate thresholds in the sediment-slurries when dominated by different TEAPs. Based on the characterization, the sediments were dominated by methanogenesis, consistent with field observations. Interestingly, in the threshold experiments, similar acetate thresholds were observed under methanogenic conditions and in chlorinated-aliphatic degrading microcosms, although thermodynamics predict lower thresholds under the latter conditions. Therefore, this study demonstrated some of the potential, as well as complications, in using and interpreting acetate thresholds as an indicator of the dominant TEAP

Using staged teaching and assessment approaches to facilitate inter-university collaboration and problem-based learning

This article describes the segmented module design and problem-based learning approaches employed to enable parts of a higher education environmental health module (course) to be shared between universities in Wales, Northern Ireland, and Australia. The module requires students to identify the needs and assets of a community then design community-based interventions to address problems and undertake an evaluation of those interventions.Accreditation body and the degree program learning outcome requirements in the UK and Australia were found to hold many comparable knowledge, skills, and graduate attribute criteria, eliminating a potential barrier for international learning and teaching collaboration between higher education institutions. Instead, barriers to collaboration were associated with institutional issues and practicalities such as timetabling and assessment requirements. Taking a segmented approach to module design allowed staged and varied levels of collaboration between participating institutions, all delivering modules (courses) with similar learning outcomes. This provided a more sustainable environment to facilitate shared learning and teaching and fostered closer relations between programs, within these constraining factors.Students using problem-based learning and its group-working component exhibited the development of leadership, communication, and independent learning skills