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Microcystin-LR (MC-LR) is a toxin produced by cyanobacteria that can bloom in freshwater supplies. This study describes a new strategy for remediation of MC-LR that combines linearization of the toxin using microcystinase A, MlrA, enzyme with rejection of linearized byproducts using membrane filtration. The MlrA enzyme was expressed in Escherichia coli (E. coli) and purified via a His-tag with 95% purity. Additionally, composite membranes made of 95% polysulfone and 5% sulfonated polyether ether ketone (SPEEK) were fabricated and used to filter a solution containing cyclic and linearized MC-LR. Tests were also performed to measure the adsorption and desorption of MC-LR on polysulfone/SPEEK membranes. Liquid chromatography-mass spectrometry (LC-MS) was used to characterize the progress of linearization and removal of MC-LR. Results indicate that the MlrA was successful at linearizing MC-LR. Membrane filtration tests showed rejection of 97% of cyclic MC-LR and virtually all linearized MC-LR, with adsorption to the membranes being the main rejection mechanism. Adsorption/desorption tests indicated that methanol could be used to strip residual MC-LR from membranes to regenerate them. This study demonstrates a novel strategy of remediation of microcystin-tainted water, combining linearization of MC-LR to a low-toxicity byproduct along with removal by membrane filtration. 

Wetland treatment systems are used extensively across the world to mitigate surface runoff. While wetland treatment for nitrogen mitigation has been comprehensively reviewed, the implications of common-use pesticides and antibiotics on nitrogen reduction remain relatively unreviewed. Therefore, this review seeks to comprehensively assess the removal of commonly used pesticides and antibiotics and their implications for nitrogen removal in wetland treatment systems receiving non-point source runoff from urban and agricultural landscapes. A total of 181 primary studies were identified spanning 37 countries. Most of the reviewed publications studied pesticides (n = 153) entering wetlands systems, while antibiotics (n = 29) had fewer publications. Even fewer publications reviewed the impact of influent mixtures on nitrogen removal processes in wetlands (n = 16). Removal efficiencies for antibiotics (35–100%), pesticides (−619–100%), and nitrate-nitrogen (−113–100%) varied widely across the studies, with pesticides and antibiotics impacting microbial communities, the presence and type of vegetation, timing, and hydrology in wetland ecosystems. However, implications for the nitrogen cycle were dependent on the specific emerging contaminant present. A significant knowledge gap remains in how wetland treatment systems are used to treat non-point source mixtures that contain nutrients, pesticides, and antibiotics, resulting in an unknown regarding nitrogen removal efficiency as runoff contaminant mixtures evolve. 

A recently launched National Science Foundation Research Traineeship (NRT) aims to enhance graduate education by integrating research and professional skill development within a diverse, inclusive and supportive academy. This contribution will describe three initial interventions within this NRT, namely, an onboarding and orientation event, a career exploration symposium, and a multidisciplinary introductory course. In addition, the assessment of each of these interventions – and the outcomes thereof – will be presented and discussed. Prior to the onboarding and orientation event, trainees received the event’s agenda and checklists summarizing pre- and post-event assignments. Pre-event assignments were designed to familiarize trainees with the NRT, the process of drafting an individual development plan (IDP), and the consent form required for traineeship evaluation purposes. During the event – held online due to COVID-19 – and following introductions, trainees were given the opportunity to ask questions stemming from the pre-event assignments. Subsequently, trainees were introduced to several tools (e.g., checklists as well as sample developmental network maps and mentoring contracts) to guide and track their development and progression through the traineeship. The event concluded with a discussion on topics that also constituted post-event assignments, including registering and preparing for both the career exploration symposium and the multidisciplinary introductory course. Survey data collected after the event indicated that trainees valued the opportunity to learn more about the NRT, ask questions, and meet faculty who expressed a commitment to student success. Shortly thereafter, trainees attended a career exploration symposium and moderated sessions featuring speakers representing careers of interest. Indeed, the symposium was purposely designed to expose trainees to a wide range of career pathways. In addition, practical career tools and skills for STEM professionals were discussed in several breakout sessions. Finally, the symposium ended with a panel discussion comprising four diverse and accomplished recent Ph.D. graduates, who discussed mental health and communication issues prior to answering questions asked by trainees. Trainee responses to a post-symposium survey were also positive as trainees reported the following: an increase in knowledge of career paths and hiring sectors, an appreciation for the diversity of the presenters and career paths, and the attainment of at least one new skill or strategy they felt would aid in their graduate school success. In their first semester in the NRT, trainees take an interdisciplinary course covering the high priority convergent research topic targeted by the traineeship. This course is co-taught by faculty of seven different departments and is composed of four units, each focused on a research question requiring extensive interdisciplinary collaboration to be answered. Teams of at least three core faculty with the cumulative expertise needed to answer each question co-teach each unit, emphasizing concepts that students must understand to address the question at hand. During this course, four multi-departmental interdisciplinary student teams are formed, each focusing on – and conducting a critical review of the literature in – one of the research questions. Indeed, emphasis is placed on providing students with the knowledge and tools to find, critically evaluate, summarize, and present literature on the topic. 

(1) Different methods have been applied to fabricate polymeric membranes with non-solvent induced phase separation (NIPS) being one of the mostly widely used. In NIPS, a solvent or solvent blend is required to dissolve a polymer or polymer blend. N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide (DMF) and other petroleum-derived solvents are commonly used to dissolve some petroleum-based polymers. However, these components may have negative impacts on the environment and human health. Therefore, using greener and less toxic components is of great interest for increasing membrane fabrication sustainability. The chemical structure of membranes is not affected by the use of different solvents, polymers, or by the differences in fabrication scale. On the other hand, membrane pore structures and surface roughness can change due to differences in diffusion rates associated with different solvents/co-solvents diffusing into the non-solvent and with differences in evaporation time. (2) Therefore, in this review, solvents and polymers involved in the manufacturing process of membranes are proposed to be replaced by greener/less toxic alternatives. The methods and feasibility of scaling up green polymeric membrane manufacturing are also examined. 

Graduate training often takes a monodisciplinary approach that is not informed by best practices, ignores the needs and preferences of students, and overlooks the increasingly interdisciplinary and international nature of research. This is unfortunate, particularly since graduate education that is fully integrated with interdisciplinary research can help students become part of a trained and diverse workforce equipped to meet society’s many challenges. Against this backdrop, a National Science Foundation Research Traineeship (NRT) program is being established at the University of Kentucky leveraging the most effective instruments for the training of STEM professionals, such as network-based graduate student mentoring and career preparation encompassing both technical and professional skillsets. Briefly, the training graduate students will receive – in a way that is fully integrated with the research they perform – includes: 1) tools such as individual development plans and developmental network maps; 2) a multi-departmental and interdisciplinary course on research-related content; 3) a seminar course on transferrable skills (ethics, research, communication, teaching, mentoring, entrepreneurship, teamwork, management, leadership, outreach, etc.); 4) a certificate to be awarded once students complete the two courses above and garner additional credits from an interdisciplinary curriculum of research-related courses; 5) summer internships at other departments and at external institutions (other universities, industry, national laboratories) nationwide or abroad; 6) an annual research-related symposium including all elements of a scientific conference; 7) internal collaborative research grants for participants to fund and pursue their own ideas; 8) fields trips to facilities related to the research; and 9) coaching on job hunting as well as résumé, motivation letter and interview preparation. Since a workforce equipped to meet society’s challenges must be both well trained and diverse, multiple initiatives will ensure that this NRT will broaden participation in STEM. Recruitment-wise, close collaboration with a number of entities will provide this NRT with a broad recruitment pool of talented and diverse students. Moreover, collaboration with these entities will provide trainees with ample opportunities to acquire, practice and refine their professional skills, as trainees present their results and recruit in conferences, meetings and outreach events organized by these entities, become members and/or join their leadership, and expand their professional and mentoring network in the process. In addition, minority trainees will be surveyed periodically to probe their feelings of well-being, preparation, acceptance, belonging and distress, as well as their perception of how well structured their departments and programs are. According to recent literature, these factors determine whether or not they perform (i.e., publish) at rates comparable to their male majority peers. Saliently, the evaluation of the educational model employed will afford a comprehensive understanding not only of the academy components that were more utilized and impactful, but will reveal the individual mentoring and skill-building facets of the program driving its successful implementation. The evaluation plan includes outcomes, performance measures, an evaluation timetable, benchmarks and a description of how formative evaluation will improve practice, the evaluation process also extending to research activities.