Toxicity evaluation of natural samples from the vicinity of rice fields using two trophic levels

An ecotoxicological screening of environmental samples collected in the vicinity of rice fields followed a combination of physical and chemical measurements and chronic bioassays with two freshwater trophic levels (microalgae: Pseudokirchneriella subcapitata and Chlorella vulgaris; daphnids: Daphnia longispina and Daphnia magna). As so, water and sediment/soil elutriate samples were obtained from three sites: (1) in a canal reach crossing a protected wetland upstream, (2) in a canal reach surrounded by rice fields and (3) in a rice paddy. The sampling was performed before and during the rice culture. During the rice cropping, the whole system quality decreased comparatively to the situation before that period (e.g. nutrient overload, the presence of pesticides in elutriates from sites L2 and L3). This was reinforced by a significant inhibition of both microalgae growth, especially under elutriates. Contrary, the life-history traits of daphnids were significantly stimulated with increasing concentrations of water and elutriates, for both sampling periods.     

Self-reported seatbelt use,United States, 2002–2010: Does prevalence vary by state and type of seatbelt law?

ProblemMotor-vehicle crashes are a leading cause of death in the United States. Seatbelts are highly effective in preventing serious injury and death in the event of a crash. Not all states have primary enforcement of seatbelt laws.MethodsData from the 2002, 2006, 2008, and 2010 Behavioral Risk Factor Surveillance System were used to calculate prevalence of seatbelt use by state and type of state seatbelt law (primary vs. secondary enforcement).Results and discussionSelf-reported seatbelt use among adults in the United States increased steadily between 2002 and 2010, with the national prevalence reaching 87% in 2010. Overall, seatbelt use in 2010 was 9 percentage points higher in the states with primary enforcement laws than in the states with secondary enforcement laws (89% vs. 80%). Impact on industry: Primary enforcement seatbelt laws and enhanced enforcement of seatbelt laws are proven strategies for increasing seatbelt use and reducing traffic fatalities.     

Differential routing of ‘new’ nitrogen toward higher trophic levels within the marine food web of the Gulf of Aqaba, Northern Red Sea

Mesozooplankton communities in the meso-oligotrophic Gulf of Aqaba, Northern Red Sea, were investigated over a 2 years period (2005–2007) with emphasis on the trophodynamic relations among different taxonomic groups ranging from primary consumers to carnivorous predators. Based on stable isotope analyses, we present evidence for a strong contribution of ‘new’ nitrogen mainly derived from the utilization of aerosol nitrate by unicellular cyanobacteria especially during summer stratification and the propagation of exceptionally low δ¹⁵N onto higher trophic levels. In contrast, N₂-fixation by diazotrophs seemed to play a minor role, while the utilization of deep water nitrate by cyanobacteria and eukaryotic algae might be of importance during winter mixing. Based on ¹⁵N enrichment of consumers, clear differences between exclusively herbivorous organisms (doliolids, appendicularians, pteropods) and those with omnivorous feeding modes were detected. The category of omnivores comprised a large variety of taxons ranging from small meroplanktonic larvae to non-calanoid copepods (harpacticoids, cyclopoids and poecilostomatoids) that together form a diverse and complex community with overlapping feeding modes. In addition, distinct seasonality patterns in δ¹⁵N of copepods were found showing elevated trophic positions during periods of winter mixing, which were most pronounced for non-calanoid copepods. In general, feeding modes of omnivores appeared rather unselective, and relative contributions of heterotrophic protists and degraded material to the diets of non-calanoid copepods are discussed. At elevated trophic positions, four groups of carnivore predators were identified, while calanoid copepods and meroplanktonic predators showing lowest ¹⁵N enrichment within the carnivores. The direct link between ‘new’ nitrogen utilization by primary producers and the ¹⁵N enrichment of consumers in the planktonic food web of the Gulf of Aqaba emphasizes the significant contribution of ‘new’ nitrogen to the nitrogen budget and ecosystem functions in subtropical and tropical oligotrophic oceans.     

The Ergonomic Program Implementation Continuum (EPIC): Integration of health and safety - A process evaluation in the healthcare sector

IntroductionThis article presents a health and safety intervention model and the use of process evaluation to assess a participatory ergonomic intervention.MethodThe effectiveness of the Ergonomic Program Implementation Continuum (EPIC) was assessed at six healthcare pilot sites in Ontario, Canada. The model provided a framework to demonstrate evaluation findings.ResultsParticipants reported that EPIC was thorough and identified improvements related to its use. Participants believed the program contributed to advancing an organizational culture of safety (COS). Main barriers to program uptake included resistance to change and need for adequate funding and resources. The dedication of organizational leaders and consultant coaches was identified as essential to the program's success.Impact on IndustryIn terms of impact on industry, findings contribute to the evidence-based knowledge of health and safety interventions and support use of the framework for creating a robust infrastructure to advance organizational COS and link staff safety and wellness with patient safety in healthcare.     

Using PCDD/F congener patterns to determine the source of elevated TEQ concentrations in cows milk: a case study

PCDD/F congener profiles have been used to determine the source of elevated TEQ concentrations in cows' milk collected in the vicinity of several industrial sites. Principal components analysis and modelling of the air-to-milk transfer of individual PCDD/F congeners have shown that the milk fingerprint was related to that of sediment taken from the River Rother adjacent to the farm where the cows had grazed. It is suggested that sediment from the river had been washed onto the grazing land during periods of flooding, and this had been ingested by the grazing cows. This pathway could represent an important route of contaminant intake for livestock grazing on the regularly inundated floodplains of rivers containing contaminated sediments.     

Flow and diffusion measurements in natural porous media using magnetic resonance imaging

Flow and diffusion of water in natural porous media, quartz sand, and calcareous gravel were measured using a 1.5-T clinical magnetic resonance tomograph. The spatial resolution of the dynamic measurements was 1.32 x 1.32 x 5 mm3, and the time between two cross-sectional measurements was approximately 10 s. The measured coefficients of molecular diffusion for water were in good agreement with theoretical data. Flow was measured without any tracer at velocities between 0.15 and 6.67 mm/s. The results, based on a calibration within one part of the column, were in good agreement with data obtained from a tracer experiment and from a numerical model. It was possible to measure the flow velocity in larger pores and preferential flow paths directly. The results of the flow measurements in smaller pores reflected the mean velocity within that volume element. In that case the obtained values were close to the average linear velocity. Since the time resolution is high a monitoring of flow processes is possible. The pore space was imaged with a spatial resolution of 0.5 x 0.5 x 0.5 mm3. Here, the porosity of pores that are larger than 0.2 mm can be measured directly; for smaller pores a calibration is necessary.