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Nitrifying Microorganisms Linked to Biotransformation of Perfluoroalkyl Sulfonamido Precursors from Legacy Aqueous Film-Forming Foams
Get PDFDrinking water supplies across the United States have been contaminated by firefighting and fire-training activities that use aqueous film-forming foams (AFFF) containing per- and polyfluoroalkyl substances (PFAS). Much of the AFFF is manufactured using electrochemical fluorination by 3M. Precursors with six perfluorinated carbons (C6) and non-fluorinated amine substituents make up approximately one-third of the PFAS in 3M AFFF. C6 precursors can be transformed through nitrification (microbial oxidation) of amine moieties into perfluorohexane sulfonate (PFHxS), a compound of regulatory concern. Here, we report biotransformation of the most abundant C6 sulfonamido precursors in 3M AFFF with available commercial standards (FHxSA, PFHxSAm, and PFHxSAmS) in microcosms representative of the groundwater/surface water boundary. Results show rapid (\u3c1 day) biosorption to living cells by precursors but slow biotransformation into PFHxS (1–100 pM day–1). The transformation pathway includes one or two nitrification steps and is supported by the detection of key intermediates using high-resolution mass spectrometry. Increasing nitrate concentrations and total abundance of nitrifying taxa occur in parallel with precursor biotransformation. Together, these data provide multiple lines of evidence supporting microbially limited biotransformation of C6 sulfonamido precursors involving ammonia-oxidizing archaea (Nitrososphaeria) and nitrite-oxidizing bacteria (Nitrospina). Further elucidation of interrelationships between precursor biotransformation and nitrogen cycling in ecosystems would help inform site remediation efforts
Evolving trend of media literacy research: A bibliometric analysis
Get PDFIn the digital internet age, media literacy (ML) continues to be updated to accommodate change and keep up with the times. Discovering the most recent developments and trends in this field is essential to provide new research perspectives. In this study, 776 ML studies spanning 21 years (2000-2021) were analyzed using the VOS viewer, a program for bibliometric analysis. In tandem with the high number of citations, the research indicates that the interest of researchers in this topic is growing. In the past six years, media and information literacy, citizenship, anti-colonial, and communication and education have been the most frequently cited keywords in media literacy studies. The most frequently cited authors in the study are the focal point of the discussion. The new subtopics broaden the study topic’s scope and foundation. Penn State University Harrisburg, University of California, Los Angeles, Salzburg Global Seminar, and Emerson College are the most frequently cited institutions. On this basis, the study discusses the future direction of media literacy research and makes corresponding recommendations
The BBNJ agreement and liability
No full textThe Biodiversity Beyond National Jurisdiction (BBNJ) negotiations are approaching the final phase, with significant urgency to conclude an agreement. But the current draft text lacks provisions for liability and compensation. This short communication investigates that absence, and its impact on consistency with UNCLOS and implementation effectiveness. It also considers existing models for liability and compensation, and questions why the Group of 77+China coalition has backed off its insistence on such provisions. In other words, the paper answers the “what,” “why,” and “how” for the inclusion of liability and compensation in the BBNJ agreement
A global review of legal protection mechanisms for the management of surf breaks
Get PDFLegal protection has become essential for managing the world\u27s surf breaks much as it has for other marine and coastal protected areas. This paper presents the first systematic review of global developments in this field. We used a keyword literature search and thematic content analysis to characterise legal protection mechanisms that are designed for surf breaks or have been specifically applied to address surf break protection needs. They are currently found in six countries, protect over 500 surf breaks, and include examples of single-location mechanisms (e.g., Malibu in USA, Punta de Lobos in Chile) and national-level protection mechanisms addressing multiple surf breaks (e.g., New Zealand and Peru). Across all examples we identified 63 discrete themes that can be drawn upon to design and communicate protection measures and present these in a typology that highlights contributing ideas. Thematic analysis identified a major distinction between process and outcome-based requirements. More comprehensive protections can be recognised by attention to a wider range of threat classes and in the detail provided for decision support, with the two ideally working together to identify the minimum assessment requirements for development proposals. Variation in levels of protection is a key topic for consideration as is the process by which locations are identified or qualified for legal protections to apply. There is also a need to evaluate the effectiveness of provisions already in place, carrying with it the need for outcomes-based monitoring which is currently rare
DNA assays for genetic discrimination of three Phragmites australis subspecies in the United States
Get PDFPremise: To genetically discriminate subspecies of the common reed (Phragmites australis), we developed real-time quantitative (qPCR) assays for identifying P. australis subsp. americanus, P. australis subsp. australis, and P. australis subsp. berlandieri.
Methods and Results: Utilizing study-generated chloroplast DNA sequences, we developed three novel qPCR assays. Assays were verified on individuals of each subspecies and against two non-target species, Arundo donax and Phalaris arundinacea. One assay amplifies only P. australis subsp. americanus, one amplifies P. australis subsp. australis and/or P. australis subsp. berlandieri, and one amplifies P. australis subsp. americanus and/or P. australis subsp. australis. This protocol enhances currently available rapid identification methods by providing genetic discrimination of all three subspecies.
Conclusions: The newly developed assays were validated using P. australis samples from across the United States. Application of these assays outside of this geographic range should be preceded by additional testing