Method to Partition Between Attached and Unattached E. coli in Runoff From Agricultural Lands 1

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72554/1/j.1752-1688.2008.00262.x.pd

Chlorinated phenols control the expression of the multidrug resistance efflux pump MexAB–OprM in Pseudomonas aeruginosa by interacting with NalC

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91122/1/MMI_7544_sm_FigS1-4_TabS1-2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/91122/2/j.1365-2958.2011.07544.x.pd

Sensor‐mediated granular sludge reactor for nitrogen removal and reduced aeration demand using a dilute wastewater

A sensor‐mediated strategy was applied to a laboratory‐scale granular sludge reactor (GSR) to demonstrate that energy‐efficient inorganic nitrogen removal is possible with a dilute mainstream wastewater. The GSR was fed a dilute wastewater designed to simulate an A‐stage mainstream anaerobic treatment process. DO, pH, and ammonia/nitrate sensors measured water quality as part of a real‐time control strategy that resulted in low‐energy nitrogen removal. At a low COD (0.2 kg m−3 day−1) and ammonia (0.1 kg‐N m−3 day−1) load, the average degree of ammonia oxidation was 86.2 ± 3.2% and total inorganic nitrogen removal was 56.7 ± 2.9% over the entire reactor operation. Aeration was controlled using a DO setpoint, with and without residual ammonia control. Under both strategies, maintaining a low bulk oxygen level (0.5 mg/L) and alternating aerobic/anoxic cycles resulted in a higher level of nitrite accumulation and supported shortcut inorganic nitrogen removal by suppressing nitrite oxidizing bacteria. Furthermore, coupling a DO setpoint aeration strategy with residual ammonia control resulted in more stable nitritation and improved aeration efficiency. The results show that sensor‐mediated controls, especially coupled with a DO setpoint and residual ammonia controls, are beneficial for maintaining stable aerobic granular sludge.Practitioner pointsTight sensor‐mediated aeration control is need for better PN/A.Low DO intermittent aeration with minimum ammonium residual results in a stable N removal.Low DO aeration results in a stable NOB suppression.Using sensor‐mediated aeration control in a granular sludge reactor reduces aeration cost.Multiple metabolic pathways and competition for nitrite exist in the treatment of anaerobically pretreated mainstream wastewater using a granular sludge reactor.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155879/1/wer1296_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155879/2/wer1296.pd

Elucidating the impact of microbial community biodiversity on pharmaceutical biotransformation during wastewater treatment

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146445/1/mbt212870.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146445/2/mbt212870_am.pd

Prevalence of Infection-Competent Serogroup 6 \u3cem\u3eLegionella pneumophila\u3c/em\u3e within Premise Plumbing in Southeast Michigan

Coinciding with major changes to its municipal water system, Flint, MI, endured Legionnaires’ disease outbreaks in 2014 and 2015. By sampling premise plumbing in Flint in the fall of 2016, we found that 12% of homes harbored legionellae, a frequency similar to that in residences in neighboring areas. To evaluate the genetic diversity of Legionella pneumophila in Southeast Michigan, we determined the sequence type (ST) and serogroup (SG) of the 18 residential isolates from Flint and Detroit, MI, and the 33 clinical isolates submitted by hospitals in three area counties in 2013 to 2016. Common to one environmental and four clinical samples were strains of L. pneumophila SG1 and ST1, the most prevalent ST worldwide. Among the Flint premise plumbing isolates, 14 of 16 strains were of ST367 and ST461, two closely related SG6 strain types isolated previously from patients and corresponding environmental samples. Each of the representative SG1 clinical strains and SG6 environmental isolates from Southeast Michigan infected and survived within macrophage cultures at least as well as a virulent laboratory strain, as judged by microscopy and by enumerating CFU. Likewise, 72 h after infection, the yield of viable-cell counts increased \u3e 100-fold for each of the representative SG1 clinical isolates, Flint premise plumbing SG6 ST367 and -461 isolates, and two Detroit residential isolates. We verified by immunostaining that SG1-specific antibody does not cross-react with the SG6 L. pneumophila environmental strains. Because the widely used urinary antigen diagnostic test does not readily detect non-SG1 L. pneumophila, Legionnaires’ disease caused by SG6 L. pneumophila is likely underreported worldwide

Phenotypic variations in persistence and infectivity between and within environmentally transmitted pathogen populations impact population-level epidemic dynamics

Abstract Background Human pathogens transmitted through environmental pathways are subject to stress and pressures outside of the host. These pressures may cause pathogen pathovars to diverge in their environmental persistence and their infectivity on an evolutionary time-scale. On a shorter time-scale, a single-genotype pathogen population may display wide variation in persistence times and exhibit biphasic decay. Methods We use a transmission modeling framework to develop an infectious disease model with biphasic pathogen decay. We take a differential algebra approach to assessing model identifiability, calculate basic reproduction numbers by the next generation method, and use simulation to explore model dynamics. Results For both long and short time-scales, we demonstrate that epidemic-potential-preserving trade-offs have implications for epidemic dynamics: less infectious, more persistent pathogens cause epidemics to progress more slowly than more infectious, less persistent (labile) pathogens, even when the overall risk is the same. Using identifiability analysis, we show that the usual disease surveillance data does not sufficiently inform these underlying pathogen population dynamics, even when combined with basic environmental monitoring data. However, risk could be indirectly ascertained by developing methods to separately monitor labile and persistent subpopulations. Alternatively, determining the relative infectivity of persistent pathogen subpopulations and the rates of phenotypic conversion will help ascertain how much disease risk is associated with the long tails of biphasic decay. Conclusion A better understanding of persistence–infectivity trade-offs and associated dynamics can improve our ecological understanding of environmentally transmitted pathogens, as well as our risk assessment and disease control strategies.https://deepblue.lib.umich.edu/bitstream/2027.42/149181/1/12879_2019_Article_4054.pd

Effluent Organic Nitrogen (EON): Bioavailability and Photochemical and Salinity-Mediated Release

The goal of this study was to investigate three potential ways that the soluble organic nitrogen (N) fraction of wastewater treatment plant (WWTP) effluents, termed effluent organic N (EON), could contribute to coastal eutrophication - direct biological removal, photochemical release of labile compounds, and salinity-mediated release of ammonium (NH4+). Effluents from two WWTPs were used in the experiments. For the bioassays, EON was added to water from four salinities (∼0 to 30) collected from the James River (VA) in August 2008, and then concentrations of N and phosphorus compounds were measured periodically over 48 h. Bioassay results, based on changes in DON concentrations, indicate that some fraction of the EON was removed and that the degree of EON removal varied between effluents and with salinity. Further, we caution that bioassay results should be interpreted within a broad context of detailed information on chemical characterization. EON from both WWTPs was also photoreactive, with labile NH4+ and dissolved primary amines released during exposure to sunlight. We also present the first data that demonstrate that when EON is exposed to higher salinities, increasing amounts of NH4+ are released, further facilitating EON use as effluent transits from freshwater through estuaries to the coast

Between platonic love and internet pornography

The article sets out to show how an holistic approach in matters of sexuality is always more helpful than one-sided approaches. On the issue of internet pornography, the authors suggest that the recent anti-masturbation online movement ‘no fapping’ is based on wrong conclusions from insufficient evidence. We suggest that a holistic approach is called for, with emphasis on the embodied human. Abstinence or what is understood by ‘Platonic love’ is not a solution, according to Plato himself. From a phenomenological perspective, we suggest owning up to our strange bodies and habitualising sexual activity