Subsurface-flow constructed wetlands, sand filters, and peat filters near Duluth, Minnesota, were studied to determine their seasonal performance for removing pathogens from wastewater. Influent was a high-strength septic tank effluent (mean values of 5-day biochemical oxygen demand, total nitrogen, and total phosphorus were 294, 96, and 15 mg/L, respectively) at the Natural Resources Research Institute's alternative treatment system test facility in northern Minnesota. Each treatment system was inoculated with cultures of Salmonella choleraesuis (serotype typhimurium) for 5 to 7 consecutive days in summer and winter during 1998 to 1999. After the seeding, outflow samples were taken until Salmonella counts were sustained at background levels. The removal of Salmonella was calculated for each system, although the exact removal mechanisms were not determined. During the summer, the wetlands removed 99.6 to 99.999 4% (2.4 to 5.3 log 10 reduction) of the culturable Salmonella. The sand filters demonstrated a greater than 7 log 10 removal of Salmonella cells, whereas the peat filters were responsible for a greater than 8 log 10 loss of cells. Fewer Salmonella cells were removed by all of these systems during the winter, although the pattern of removal was similar to their summer operation. During the winter, the wetlands and sand filters removed greater than 1 log 10 of culturable cells, but the peat filters were responsible for a greater than 5 log 10 loss of cells. Fecal coliform removal patterns reflected those for Salmonella by treatment systems for summer and winter periods. Based on Salmonella and fecal coliform removal, the peat filters operated most effectively followed by the sand filters and the constructed wetlands. Water Environ. Res., 73, 204 (2001).

The use of a clinical utility index (CUI) was proposed in order to compare two calcium channel alpha2delta ligands that were in development for the treatment of insomnia. The important attributes included in the CUI were two measures of residual sedation and five measures of efficacy (wake after sleep onset, sleep quality, sleep latency, and sleep stages (stage 1 and stages 3-4)). Dose-response analyses were conducted on each end point, and a sensitivity analysis was conducted to determine a clinically meaningful difference in CUI. Nonparametric bootstrap parameters were used to build confidence intervals (CIs). Peak CUI (80% CI) was 0.345 (0.25-0.43), observed at a dose of approximately 30 mg with the lead compound and 0.436 (0.35-0.52) observed at >600-mg dose for the backup. Although CUI was slightly greater for the backup, peak CUI values were observed at doses that were not considered viable, and therefore development of the ligand was discontinued. The use of the CUI allowed an efficient, quantitative, and transparent decision.

Viral contamination of public waters is a leading health concern around the world, including in Minnesota where cold climate, abundant onsite systems on poor or thin soils, and abundant surface water resources present a significant risk of wastewater pathogens reaching sensitive water sources. Three alternative onsite treatment systems, a sand filter, peat filter and subsurface-flow constructed wetland (CW) at a field research site were evaluated for seasonal virus removal by seeding each with MS2 bacteriophage. The sand and peat filters and CW removed 2.7, 7.0, and 1.4 log10 of MS2, respectively, during summer and 1.8 and 6.9 log for the sand and peat filter during winter (CW not seeded). Somatic coliphage reductions for the sand filter, peat filter and CW were 2.9, 3.5, 1.0 log10 in summer, and 1.5, 2.8, 0.7 log10 during winter, respectively over a 3 year period. During this period, fecal coliform log10 reductions were 2.9, 4.6, 2.0 in summer for the sand and peat filters and CW, and 2.0, 4.6, 1.6 in winter. The peat filter was the most effective system for removing MS2, somatic coliphage and fecal coliforms during both winter and summer but all systems removed >90% of viruses throughout the year.

Participants (N = 202) were students at a college in the northeastern United States who participated in the 2010 Core Alcohol and Drug survey. Data were collected on prepartying behavior, preparty social norms, and individual-difference variables. Using multivariate logistic and least-squares regression, it was found that descriptive social norms were associated with prepartying in women and injunctive social norms were associated with prepartying in men. Prepartying also was found to be negatively related to underage status and GPA in women and positively related to Greek membership and athlete status in men. Implications for social-norms interventions and suggestions for future social-norms research are discussed.

Approximately 30% of Minnesotans use on-site systems (approximately 500,000 residences) and >50% are failing or non-compliant with regulations due to restrictive soils and site conditions. Many sites occur near lakes and streams creating health hazards and deteriorating water quality. SSF CWs have been evaluated year-round at two northern sites since 1995. The NERCC CWs simulate single homes and the Grand Lake demonstration CW treats STE from a cluster of 9 lakeshore homes. Systems were generally able to achieve design criteria of 25 mg TSS/L and 30 mg BOD5/L and the NERCC CWs required only 0.3 m of unsaturated soil to achieve consistent disinfection to <200 fecals/100 mL year round. Seeding experiments with Salmonella indicated removal efficiencies of 99.8% in summer and 95% in winter. High strength (approximately 300 mg BOD/L, 95 mg TN/L) influent at NERCC probably limited system performance, particularly N-removal (mass) which was approximately 42% in summer and 20% in winter. The data indicate CW's are a viable, year-round treatment option for homeowners in terms of performance, ease of operation, and cost but require additional maintenance related to inconsistent vegetation growth, winter insulation, and meeting concentration-based regulatory standards since they were seasonally and annually variable due to rain events, partial freezing, spring snowmelt, and summer evapotranspiration.