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Excess phosphorus (P) in wastewater effluent poses a serious threat to aquatic ecosystems and can spur harmful algal blooms. Revolving algal biofilm (RAB) systems are an emerging technology to recover P from wastewater before discharge into aquatic ecosystems. In RAB systems, a community of microalgae take up and store wastewater P as polyphosphate as they grow in a partially submerged revolving biofilm, which may then be harvested and dried for use as fertilizer in lieu of mined phosphate rock. In this work, we isolated and characterized a total of 101 microalgae strains from active RAB systems across the US Midwest, including 82 green algae, 9 diatoms, and 10 cyanobacteria. Strains were identified by microscopy and 16S/18S ribosomal DNA sequencing, cryopreserved, and screened for elevated P content (as polyphosphate). Seven isolated strains possessed at least 50% more polyphosphate by cell dry weight than a microalgae consortium from a RAB system, with the top strain accumulating nearly threefold more polyphosphate. These top P-hyperaccumulating strains include the green alga Chlamydomonas pulvinata TCF-48 g and the diatoms Eolimna minima TCF-3d and Craticula molestiformis TCF-8d, possessing 11.4, 12.7, and 14.0% polyphosphate by cell dry weight, respectively. As a preliminary test of strain application for recovering P, Chlamydomonas pulvinata TCF-48 g was reinoculated into a bench-scale RAB system containing Bold basal medium. The strain successfully recolonized the system and recovered twofold more P from the medium than a microalgae consortium from a RAB system treating municipal wastewater. These isolated P-hyperaccumulating microalgae may have broad applications in resource recovery from various waste streams, including improving P removal from wastewater.

There are relatively few comprehensive and empowering educational tools to assist people with terminal illness in addressing important end-of-life issues. Identifying this scarcity, a design team of health and multimedia professionals created an interactive, educational CD-ROM entitled Completing a Life. The primary goal of the project was to provide rich content in a style that was easy to access, understand, and use. The interactive medium of the CD-ROM enabled a large amount and wide array of material to be presented in manageable segments. These segments are connected by hyperlinks, providing self-guided control over the selection, pace, and order of material. The CD puts the learning experience in the hands of the learner. The format and design is also intended to generate a sense of empowerment, at a time and around issues often associated with a loss of control. Completing a Life covers a wide range of information for the user to choose from, spanning physical, emotional, family, and spiritual issues. A calm and comforting tone and welcoming environment enhances the users' ability to take in the information and make proactive decisions about his/her own well-being and care. The CD contains video narratives of individuals who tell their own stories of living with terminal illness. In addition to being a highly relevant means of conveying sensitive, health-related information, this collection of personal interviews may offer a form of "virtual support group" for the user. Finally, the interactive format allows stories and informational content to be linked in topic-specific ways that complement one another. [ABSTRACT FROM AUTHOR]