Extending parental mentoring using an event-triggered video intervention in rural teen drivers

Teen drivers are at high risk for car crashes, especially during their first years of licensure. Providing novice teen drivers and their parents with a means of identifying their risky driving maneuvers may help them learn from their mistakes, thereby reducing their crash propensity. During the initial phase of learning, adult or parental supervision often provides such guidance. However, once teens obtain their license, adult supervision is no longer mandated, and teens are left to themselves to continue the learning process. This study is the first of its type to enhance this continued learning process using an event-triggered video device. By pairing this new technology with parental feedback in the form of a weekly video review and graphical report card, we extend parents' ability to teach their teens even after they begin driving independently. Twenty-six 16- to 17-year-old drivers were recruited from a small U.S. Midwestern rural high school. We equipped their vehicles with an event-triggered video device, designed to capture 20-sec clips of the forward and cabin views whenever the vehicle exceeded lateral or forward threshold accelerations. Preliminary findings suggest that combining this emerging technology with parental weekly review of safety-relevant incidents resulted in a significant decrease in events for the more at-risk teen drivers. Implications for how such an intervention could be implemented within GDL are also discussed.     

Effect of initial sulfide concentration on sulfide and phenol oxidation under denitrifying conditions

The objective of this work was to evaluate the effect of the initial sulfide concentration on the kinetics and metabolism of phenol and sulfide in batch bioassays using nitrate as electron acceptor. Complete oxidation of sulfide (20 mg L(-1) of S(2-)) and phenol (19.6 mg L(-1)) was linked to nitrate reduction when nitrate was supplemented at stoichiometric concentrations. At 32 mg L(-1) of sulfide, oxidation of sulfide and phenol by the organo-lithoautotrophic microbial culture was sequential; first sulfide was rapidly oxidized to elemental sulfur and afterwards to sulfate; phenol oxidation started once sulfate production reached a maximum. When the initial sulfide concentration was increased from 20 to 26 and finally to 32 mg L(-1), sulfide oxidation was inhibited. In contrast phenol consumption by the denitrifying culture was not affected. These results indicated that sulfide affected strongly the sulfide oxidation rate and nitrate reduction.     

Effects of moisture damage and renovation on microbial conditions and pupils' health in two schools--a longitudinal analysis of five years

Airborne microbes and pupils' symptoms were monitored in a moisture-damaged (index) school and a reference school for five consecutive years. These surveys were carried out in two separate years before the renovation of the index school, during the renovation, and one and two years after the renovation. Microbial concentrations were higher in the index school than those in the reference school before and during renovation, but afterwards, the levels decreased to the level of the reference school. The effect of remediation was seen as an altered mycobiota in the index school. Year-to-year variation of microbial concentrations, probably due to climatic factors, caused a peak in both schools but their difference remained. Several symptoms were more prevalent in the moisture-damaged school than in the reference school, but the differences disappeared during the renovations. These results emphasize the importance of using a reference building in assessing the microbial conditions of a moisture damaged building. Furthermore, microbial concentrations reflected well the technical condition of the construction, but the reported symptoms of the occupants did not strictly follow the timely fluctuation in microbial conditions.     

Impact of Urban Growth and High Residential Irrigation on Streamflow and Groundwater Levels in a Peri‐Urban Semiarid Catchment

The impact of urbanization on groundwater is not simple to understand, as it depends on a variety of factors such as climate, hydrogeology, water management practices, and infrastructure. In semiarid landscapes, the urbanization processes can involve high water consumptions and irrigation increases, which in turn may contribute to groundwater recharge. We assessed the hydrological impacts of urbanization and irrigation rates in an Andean peri‐urban catchment located in Chile, in a semiarid climate. For this purpose, we built and validated a coupled surface–groundwater model that allows the verification of a strong stream–aquifer interaction in areas with shallow groundwater, higher than some sewers and portions of the stream. Moreover, we also identified a significant local recharge associated with pipe leaks and inefficient urban irrigation. From the evaluation of different future scenarios, we found a sustainable water conservation scenario will decrease the current groundwater levels, while the median flow reduces from 408 to 389 L/s, and the low flow (Q_95%) from 43 to 22L/s. Overall, our results show the relevance of integrating the modeling of surface and subsurface water resources at different spatial and temporal scales, when assessing the effect of urban development and the suitability of urban water practices.     

Stoichiometric and molecular evidence for the enrichment of anaerobic ammonium oxidizing bacteria from wastewater treatment plant sludge samples

Anammox enrichments were readily developed from seven municipal wastewater treatment plants (WWTPs) sludge, but not with methanogenic granular sludge from two agro-industrial WWTPs. Only 50 d was required for the first evidence of anammox activity from a return activated sludge obtained from a WWTP operated for nutrient removal. The molar ratios of nitrite and ammonium consumption of approximately 1.32 as well as nitrate and dinitrogen gas product ratios of approximately 0.095 provided evidence of the anammox reaction. The presence of anammox was confirmed by polymerase chain reaction (PCR) using primer sets (PLA46F and AMX820R) specific for anammox bacteria. The 16S rRNA gene fragment of anammox bacteria was detected in seven enrichment cultures (ECs) with demonstrated anammox activity but not in the original inocula from which the ECs were derived and also not in the two methanogenic sludge samples, which indicates the PCR predicted the anammox activity. Two genera, Brocadia and Kuenenia, were successfully identified as the Planctomycetes occurring in the clone libraries of successful anammox enrichments. Brocadia dominated in cultures that were respiked extensively; whereas Kuenenia predominated in cultures that were less aggressively respiked. These findings indicate that respiking management may play an important role on selecting the genus of anammox bacteria. The batch enrichment results clearly illustrate that anammox can be readily enriched from municipal sludge from a wide variety of process operations at WWTPs.