Exposure to perfluorooctane sulfonic acid (PFOS) adversely affects the life-cycle of the damselfly Enallagma cyathigerum

We evaluated whether life-time exposure to PFOS affects egg development, hatching, larval development, survival, metamorphosis and body mass of Enallagma cyathigerum (Insecta: Odonata). Eggs and larvae were exposed to five concentrations ranging from 0 to 10 000 μg/L. Our results show reduced egg hatching success, slower larval development, greater larval mortality, and decreased metamorphosis success with increasing PFOS concentration. PFOS had no effect on egg developmental time and hatching or on mass of adults. Eggs were the least sensitive stage (NOEC = 10 000 μg/L). Larval NOEC values were 1000 times smaller (10 μg/L). Successful metamorphosis was the most sensitive response trait studied (NOEC < 10 μg/L). The NOEC value suggests that E. cyathigerum is amongst the most sensitive freshwater organisms tested. NOEC for metamorphosis is less than 10-times greater than the ordinary reported environmental concentrations in freshwater, but is more than 200-times smaller than the greatest concentrations measured after accidental releases.     

First Europe-wide correlation analysis identifying factors best explaining the total nitrogen concentration in mosses

In this study, the indicative value of mosses as biomonitors of atmospheric nitrogen (N) depositions and air concentrations on the one hand and site-specific and regional factors which explain best the total N concentration in mosses on the other hand were investigated for the first time at a European scale using correlation analyses. The analyses included data from mosses collected from 2781 sites across Europe within the framework of the European moss survey 2005/6, which was coordinated by the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation). Modelled atmospheric N deposition and air concentration data were calculated using the Unified EMEP Model of the European Monitoring and Evaluation Programme (EMEP) of the Convention on Long-range Transboundary Air Pollution (CLRTAP). The modelled deposition and concentration data encompass various N compounds. In order to assess the correlations between moss tissue total N concentrations and the chosen predictors, Spearman rank correlation analysis and Classification and Regression Trees (CART) were applied. The Spearman rank correlation analysis showed that the total N concentration in mosses and modelled N depositions and air concentrations are significantly correlated (0.53 ≤ r_s ≤ 0.68, p < 0.001). Correlations with other predictors were lower than 0.55. The CART analysis indicated that the variation in the total N concentration in mosses was best explained by the variation in NH₄⁺ concentrations in air, followed by NO₂ concentrations in air, sampled moss species and total dry N deposition. The total N concentrations in mosses mirror land use-related atmospheric concentrations and depositions of N across Europe. In addition to already proven associations to measured N deposition on a local scale the study at hand gives a scientific prove on the association of N concentration in mosses and modelled deposition at the European scale.     

Treatment of exhaust fluorescent lamps to recover yttrium: experimental and process analyses

The paper deals with recovery of yttrium from fluorescent powder coming from dismantling of spent fluorescent tubes. Metals are leached by using different acids (nitric, hydrochloric and sulphuric) and ammonia in different leaching tests. These tests show that ammonia is not suitable to recover yttrium, whereas HNO(3) produces toxic vapours. A full factorial design is carried out with HCl and H(2)SO(4) to evaluate the influence of operating factors. HCl and H(2)SO(4) leaching systems give similar results in terms of yttrium extraction yield, but the last one allows to reduce calcium extraction with subsequent advantage during recovery of yttrium compounds in the downstream. The greatest extraction of yttrium is obtained by 20% w/v S/L ratio, 4N H(2)SO(4) concentration and 90°C. Yttrium and calcium yields are nearly 85% and 5%, respectively. The analysis of variance shows that acid concentration alone and interaction between acid and pulp density have a significant positive effect on yttrium solubilization for both HCl and H(2)SO(4) medium. Two models are empirically developed to estimate yttrium and calcium concentration during leaching. Precipitation tests demonstrate that at least the stoichiometric amount of oxalic acid is necessary to recover yttrium efficiently and a pure yttrium oxalate n-hydrate can be produced (99% grade). The process is economically feasible if other components of the fluorescent lamps (glass, ferrous and non-ferrous scraps) are recovered after the equipment dismantling and valorized, besides the cost that is usually paid to recycling companies for collection, treatment or final disposal of such fluorescent powders.     

Biodiversity of marine sessile epifauna at an Aegean island subject to hydrothermal activity: Milos, eastern Mediterranean Sea

Sessile macroepifauna was sampled at six rocky sites between 2 and 90 m depth with a number of different methods involving both underwater photography and collection of specimens. A total of 212 species (or varieties) were identified, belonging to seven higher taxa: poriferans (24 species), cnidarians (32), molluscs (8), serpuloidean polychaetes (33), bryozoans (90), brachiopods (4) and ascidians (21). The combined use of a varied array of sampling methods was effective in obtaining a rich faunal inventory. Deep and offshore sites tended to be richer in species than shallow and inshore sites. In all cases species richness was higher at sites closest to hydrothermal vents on the sea floor. Although there are no comparable inventories of marine sessile epifauna in the Aegean, the high number of species found, with a relatively low sampling effort in a restricted area, indicates that the marine biodiversity of this sea is not as low as traditionally believed. Received: 20 January 1999 / Accepted: 25 August 1999     

Wind- and tide-induced currents in the Stagnone lagoon (Sicily)

The hydrodynamic circulation is analyzed in the coastal lagoon of Stagnone di Marsala, a natural reserve located in the north-western part of Sicily, using both experimental measurements and numerical simulations. Field measurements of velocities and water levels, carried out using an ultrasound sensor (3D), are used to validate the numerical model. A 3D finite-volume model is used to solve the Reynolds-averaged momentum and mass balance differential equations on a curvilinear structured grid, employing the k–e{\varepsilon} turbulence model for the Reynolds stresses. The numerical analysis allows to identify the relative contribution of the forces affecting the hydrodynamic circulation inside the lagoon. In the simulations only wind and tide forces are considered, neglecting the effects of water density changes. Two different conditions are considered. In the first both the wind stress over the free-surface and the tidal motion are imposed. In the second the wind action is neglected, to separately analyze the tide-induced circulation. The comparison between the two test cases highlights the fundamental role of the wind on the hydrodynamics of the Stagnone lagoon, producing a strong vertical recirculation pattern that is not observed when the flow is driven by tides only.     

Measuring sedimentation in tidal marshes: a review on methods and their applicability in biogeomorphological studies

It is increasingly recognised that interactions between geomorphological and biotic processes control the functioning of many ecosystem types as described e.g. by the ecological theory of ecosystem engineering. Consequently, the need for specific bio-geomorphological research methods is growing recently. Much research on bio-geomorphological processes is done in coastal marshes. These areas provide clear examples of ecosystem engineering as well as other bio-geomorphological processes: Marsh vegetation slows down tidal currents and hence stimulates the process of sedimentation, while vice versa, the sedimentation controls ecological processes like vegetation succession. This review is meant to give insights in the various available methods to measure sedimentation, with special attention to their suitability to quantify bio-geomorphological interactions. The choice of method used to measure sedimentation is important to obtain the correct parameters to understand the biogeomorphology of tidal salt marshes. This review, therefore, aims to be a tool for decision making regarding the processes to be measured and the methods to be used. We, subdivide the methods into those measuring suspended sediment concentration (A), sediment deposition (B), accretion (C) and surface-elevation change (D). With this review, we would like to further encourage interdisciplinary studies in the fields of ecology and geomorphology.     

Feasibility of the hydrogen sulfide test for the assessment of drinking water quality in post-earthquake Haiti

In 2010, a magnitude 7.0 earthquake struck Haiti, severely damaging the drinking and wastewater infrastructure and leaving millions homeless. Compounding this problem, the introduction of Vibrio cholerae resulted in a massive cholera outbreak that infected over 700,000 people and threatened the safety of Haiti’s drinking water. To mitigate this public health crisis, non-government organizations installed thousands of wells to provide communities with safe drinking water. However, despite increased access, Haiti currently lacks the monitoring capacity to assure the microbial safety of any of its water resources. For these reasons, this study was designed to assess the feasibility of using a simple, low-cost method to detect indicators of fecal contamination of drinking water that could be implemented at the community level. Water samples from 358 sources of drinking water in the Léogâne flood basin were screened with a commercially available hydrogen sulfide test and a standard membrane method for the enumeration of thermotolerant coliforms. When compared with the gold standard method, the hydrogen sulfide test had a sensitivity of 65 % and a specificity of 93 %. While the sensitivity of the assay increased at higher fecal coliform concentrations, it never exceeded 88 %, even with fecal coliform concentrations greater than 100 colony-forming units per 100 ml. While its simplicity makes the hydrogen sulfide test attractive for assessing water quality in low-resource settings, the low sensitivity raises concerns about its use as the sole indicator of the presence or absence of fecal coliforms in individual or community water sources.     

Why seeking feedback from diverse sources may not be sufficient for stimulating creativity: The role of performance dynamism and creative time pressure

We explore how the impact of seeking feedback from different sources (i.e., feedback source variety) on employee creativity is shaped by perceptions of the work environment. Specifically, we argue that two contextual factors, namely, performance dynamism (Study 1) and creative time pressure (Study 2), moderate the relationship between feedback source variety and creativity such that under conditions of high performance dynamism and low creative time pressure, individuals benefit from diverse feedback information. In Study 1 (N = 1,031), the results showed that under conditions of high performance dynamism, the relationship between feedback source variety and self‐reported creativity was nonlinear, with employee creativity exponentially increasing as a function of feedback source variety. Similarly, in Study 2 (N = 181), we found that under conditions of low creative time pressure, the relationship between feedback source variety and employee creativity was nonlinear, with supervisor‐rated creative performance exponentially increasing at higher levels of feedback source variety. Such results highlight that the relationship between feedback source variety and creative performance is affected by the perceptions of the work environment in which feedback is sought.     

Yttrium recovery from primary and secondary sources: A review of main hydrometallurgical processes

Yttrium is important rare earths (REs) used in numerous fields, mainly in the phosphor powders for low-energy lighting. The uses of these elements, especially for high-tech products are increased in recent years and combined with the scarcity of the resources and the environmental impact of the technologies to extract them from ores make the recycling waste, that contain Y and other RE, a priority.The present review summarized the main hydrometallurgical technologies to extract Y from ores, contaminated solutions, WEEE and generic wastes. Before to discuss the works about the treatment of wastes, the processes to retrieval Y from ores are discussed, since the processes are similar and derived from those already developed for the extraction from primary sources.Particular attention was given to the recovery of Y from WEEE because the recycle of them is important not only for economical point of view, considering its value, but also for environmental impact that this could be generated if not properly disposal.