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Introduction Surgery in children can be difficult for patients and parents. We aimed to summarize pediatric patients' and parents' psychosocial experiences and needs in surgery. Method We used the Ovid search engine and screened 877 abstracts across three databases to extract data on pediatric patients' and parents' surgical experiences. Results Our search yielded 11 eligible studies representing 1,307 children undergoing surgery and their parents. Children's adverse experiences included psychological and behavioral changes before, during, and after surgery (e.g., anxiety, eating disturbances). Parents commonly experienced psychological distress. Children's needs related to medical and health care services, whereas parents had high information needs. Discussion Children's adverse experiences can negatively affect medical outcomes. Children's experiences are inextricably linked to their parents' and can become negatively affected by their parents' adverse experiences. Patients and parents with previous hospitalizations and surgeries had worse surgical experiences, highlighting further research in the context of chronic illness. [ABSTRACT FROM AUTHOR]

Abstract: The impact of rainfall on total gaseous mercury (TGM) flux from pavement and street dirt surfaces was investigated in an effort to determine the influence of wet weather events on mercury transport in urban watersheds. Street dirt and pavement are common urban ground surfaces that concentrate many substances (eroded soil, leaf and vegetation litter, automobile debris, industrial atmospheric fallout) which can contain elevated mercury concentrations. In this study, the primary analyses included (i) observing the time series flux of TGM from pavement and street dirt following surface wetting and (ii) determining if wet deposition provides a fresh source of mercury that is available for release (emission) when applied to these surfaces. Application of de-ionized water (DI) and rainwater both induced an immediate 65% increase in TGM emission from pavement (from 0.5 to 1.4ngm−2 h−1 [based on averages]). For street dirt, an immediate 70% increase in emission was induced following DI water application (from 3.0 to 9.0ngm−2 h−1 [based on averages]) and an immediate 30% increase in emission following rainwater application (from 4.5 to 6.5ngm−2 h−1 [based on averages]). Both surfaces showed continuous elevated release of TGM following the initial water application stage. There was a decrease in emission as the pavement surface dried. Despite the difference in immediate TGM emission from street dirt using both solutions, statistical evaluation indicated there was no prolonged difference. This suggests that mercury in rainwater was not available for re-emission when applied to these surfaces, at least for the time frame studied (2h after water application). Therefore, it is likely that the elevated TGM emission following water application resulted primarily from pre-existing mercury. Removal of pre-existing mercury by water application followed a zero order process for both surfaces; however, removal rates were much different for each surface (k =0.26ngm−2 min−1 for street dirt; k =0.03ngm−2 min−1 for pavement). Results from laboratory surface washing experiments revealed only 0.1% of all available surface-bound mercury on pavement was removed by surface emission 90min after a simulated light rainfall event (0.13cm of rainfall). [Copyright &y& Elsevier]

The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO3 −-N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman ρ =0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r =0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r 2 =0.73, with an overall 10 ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem. [Copyright &y& Elsevier]

Abstract: Experiments utilizing meteorologically normalized sampling conditions were used to illustrate the role and function of urban pavement, bare soil and turf grass surface properties with respect to the air-surface exchange of total gaseous Hg (TGM). After ensuring uniform meteorological effects to each surface, resultant TGM fluxes from turf grass, bare soil and pavement were specifically representative of their diverse physical and biogeochemical properties. Results spanning the entire sampling year show distinct TGM flux signatures for each surface (5.69±5.79 (ng/m2 h) for bare soil, 0.53±1.25 for turf grass, 0.26±0.41 for pavement). Based on medians, the surface limitations of pavement decreased TGM flux by a factor of 22 compared to bare soil and by a factor of 2 compared to turf grass. Turf surface limitations decreased TGM flux by a factor of 11 compared to bare soil. By comparing these results to a parallel study, meteorological effects were found to develop 24% of the TGM flux signature for pavement, 53% for turf and 60% for bare soil. The remaining percentage contributions to each TGM flux signature were from the cumulative surface property effects of each surface. These results suggest that the greater the TGM flux magnitude for a particular surface, the more measurements are needed under a wide variety of meteorological conditions to develop a broad understanding of its TGM flux characteristics. Seasonal observation allowed closer investigation of a large shift to TGM deposition for the turf surface during the fall season. The large shift toward deposition was suspected to be linked to the formation of a thatch layer on the unexposed soil surface just beneath the turf layer. [Copyright &y& Elsevier]

Abstract: Total gaseous mercury flux measurements were carried out over three urban ground surfaces for 1 year in Tuscaloosa, AL, USA. The objective was to provide insight into the characteristics of gaseous mercury flux from urban surface covers. Bare soil, grass, and pavement surfaces were sampled as the most representative terrestrial surfaces throughout Tuscaloosa. Measurements were quantified over diurnal and seasonal periods and relationships were developed between flux from each surface and major meteorological parameters. Averaging data over the entire year, fluxes from each surface were as follows: bare soil (6.48ng/m−2 h), pavement (0.02ng/m−2 h), and grass (0.28ng/m−2 h). Pavement and many grass fluxes were small and arguably indistinguishable from chamber blanks. The soil surface displayed the largest difference between evening and daytime flux, particularly during the spring and summer seasons (i.e., evening low (12ng/m−2 h) to daytime high (30ng/m−2 h) during summer). The grass surface showed the largest amount of atmospheric deposition, mainly during the spring and fall periods (up to −2.31ng/m−2 h), with pavement showing somewhat less (up to −1.05ng/m−2 h). Bare soil showed very little to negligible deposition. Diurnal flux variance was greater than seasonal flux variance for all surfaces. The regression results demonstrate that despite the highly dissimilar physical and geochemical make-up of pavement, bare soil, and grass, each surface displayed similar responses to time series change in meteorological parameters. However, each surface may be seasonally controlled or limited by different sets of meteorological parameters. [Copyright &y& Elsevier]

Abstract: Simultaneous measurement of gaseous elemental, reactive gaseous, and fine particulate mercury took place in Tuscaloosa AL, (urban airshed) and Cove Mountain, TN (non-urban airshed) during the summers of 2002 and 2003. The objective of this research was to (1) summarize the temporal distribution of each mercury specie at each site and compare to other speciation data sets developed by other researchers and (2) provide insight into urban and non-urban mercury speciation effects using various statistical methods. Average specie concentrations were as follows: 4.05ngm−3 (GEM), 13.6pgm−3 (RGM), 16.4pgm−3 (Hg-p) for Tuscaloosa; 3.20ngm−3 (GEM), 13.6pgm−3 (RGM), 9.73pgm−3 (Hg-p) for Cove Mountain. As a result of urban airshed impacts, short periods of high concentration for all mercury species was common in Tuscaloosa. At Cove Mountain a consistent mid-day rise and evening drop for mercury species was found. This pattern was primarily the result of un-impacted physical boundary layer movement, although, other potential impacts were ambient photochemistry and air-surface exchange of mercury. Meteorological parameters that are known to heavily impact mercury speciation were similar for the study period for Tuscaloosa and Cove Mountain except for wind speed (ms−1), which was higher at Cove Mountain. For both sites statistically significant (), inverse relationships existed between wind speed and Hg0 concentration. A weaker windspeed-Hg0 correlation existed for Tuscaloosa. By analyzing Hg concentration—wind speed magnitude change at both sites it was found that wind speed at Cove Mountain had a greater influence on Hg0 concentration variability than Tuscaloosa by a factor of 3. Using various statistical tests, we concluded that the nature of Tuscaloosa''s atmospheric mercury speciation was the result of typical urban airshed impacts. Cove Mountain showed atmospheric mercury speciation characteristics indicative of a non-urban area along with potential influence from steady regional input of mercury pollution from larger sources. [Copyright &y& Elsevier]

Abstract: We investigated the potential effects of elevated water-column sulfate (SO4) levels on heterotrophic microbial respiration and net phosphorus (P) release for soils collected from impacted and unimpacted Everglades wetlands in south Florida. Soils from three sites, ranging from low P and low SO4 to high P and high SO4 environments, were examined under controlled laboratory conditions. The soils were subjected to anaerobic incubations to evaluate net P release and organic matter decomposition in response to SO4 amendments of 32 or 96mgl−1 (0.33 and 1.0mM). Three processes have been described in the literature to explain why SO4 enrichment may lead to P release from soils under anaerobic conditions. First, alkalinization can lead to a more favorable pH environment for decomposition. For the soils examined here, alkalinization due to the hydrogen ion-consuming reaction of SO4 reduction was not a prominent mechanism. We found that pH decreased in the incubation vessels, and that increases in alkalinity were more likely attributable to calcium carbonate dissolution than SO4 reduction. Moreover, all the soils exhibited near circum-neutral pH levels, with moderate to high concentrations of native alkalinity. Second, formation of iron sulfide (FeSx) compounds has been shown to mobilize iron (Fe)-associated P. Soils from only one of the study sites had Fe concentrations that would be expected to be high enough to influence P mobility. Relatively high porewater Fe:soluble reactive P (SRP) ratios (>83:1) were observed at this site, which suggests that Fe could theoretically exert control over the release of P from the soil. However, soil P levels at this site were too low to measure any substantial influence of Fe on net P mobilization. Finally, availability of electron acceptors such as SO4 is a major determinant of decomposition rate, and thus rate of organic P release. Amending the soils with SO4 did not result in either more heterotrophic microbial respiration as measured by carbon dioxide (CO2) and methane (CH4) production, or increased net P mobilization. In two of the SO4-amended soils where post-incubation total sulfide concentrations were as high as 23.4mgl−1, SO4 addition reduced production of respiratory carbon end products, suggesting hydrogen sulfide inhibition. Moreover, limitations imposed by substrate quality and low P contributed to the lack of meaningful enhanced decomposition of organic matter with the addition of 32 or 96mg SO4 l−1 to the oligotrophic wetland soils. Even though P release did occur under anaerobic conditions for the more enriched site, addition of SO4 did not enhance P release. [Copyright &y& Elsevier]