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  • Gylling Nicolajsen posted an update 3 days, 16 hours ago

    Interactions with air pollution were not generally assessed. The few studies investigating effect modification showed stronger effects among the elderly and those socially deprived. Comparisons of health outcome prevalence between areas reported lower blood pressure and a tendency for higher obesity in populations living in warmer climates. Our review indicated interesting associations between long-term exposure to unusual temperature levels in specific areas and differences in health outcomes and cardiovascular risk factors between geographical locations with different climate, but the number of studies by design and health outcome was small. Risk of bias was identified because of the use of crude exposure assessment and inadequate adjustment for confounding. More and better designed studies, including the investigation of effect modifiers, are needed.Herein, the dimethyl phthalate (DMP) contamination, as an emerging pollutant, has been cost-effectively removed from landfill leachate through an advanced oxidation process, that is the electro-Fenton (EF) process. For this purpose, a quadratic polynomial model was developed via response surface methodology (RSM). Furthermore, the analysis of variance (ANOVA) was performed for evaluating the significance of the proposed assumptions. The actual removal rate of 99.1% was obtained with optimal values of 4 mg L-1 of initial DMP concentration, 50 mM Na2SO4, 600 μL L-1 H2O2, 8-minute electrolytic time, solution pH 3 and 6 mA cm-2 current density for the process variables and was consistent with the expected 99.6% removal rate. Satisfactory correlation coefficients were obtained, and a non-significant value of 0.0618 for model mismatch confirmed that the proposed model is extremely important and can successfully predict the effectiveness of DMP removal. The kinetics of the process and the effect of the presence of some radical scavengers were studied to understand the exact mechanism of DMP degradation. Therefore, it was observed that the reaction of hydroxyl radicals with DMPs followed the first-order kinetics model. Moreover, it was established that the optimal ratio of H2O2/Fe2+ mole was 1.6 and the electricity consumption was 0.157 kWh m-3. The elaborated treatment model used to remove DMP from landfill leachate showed that DMP contamination was effectively removed with a 95.6% removal efficiency in the investigating process.Identifying the space-time patterns of areas with a higher risk of transmission and the associated built environment and demographic characteristics during the COVID-19 pandemic is critical for developing targeted intervention measures in response to the pandemic. This study aims to identify areas with a higher risk of COVID-19 transmission in different periods in Hong Kong and analyze the associated built environment and demographic factors using data of individual confirmed cases. We detect statistically significant space-time clusters of COVID-19 at the Large Street Block Group (LSBG) level in Hong Kong between January 23 and April 14, 2020. Two types of high-risk areas are identified (residences of and places visited by confirmed cases) and two types of cases (imported and local cases) are considered. The demographic and built environment features for the identified high-risk areas are further examined. The results indicate that high transport accessibility, dense and high-rise buildings, a higher density of commercial land and higher land-use mix are associated with a higher risk for places visited by confirmed cases. More green spaces, higher median household income, lower commercial land density are linked to a higher risk for the residences of confirmed cases. The results in this study not only can inform policymakers to improve resource allocation and intervention strategies but also can provide guidance to the public to avoid conducting high-risk activities and visiting high-risk places.Climate warming is expected to enhance forest growth in cold-limited biomes while triggering reductions in drought-limited biomes. However, as temperature raises, it is unclear how temperature- and drought-growth couplings shift across elevation gradients in different biomes. We still lack comprehensive analyses on how altitude modulates the influence of temperature and drought on tree growth during the second half of the 20th century when climate warming accelerated. We compared the worldwide responses of tree growth (RWI, ring-width indices) to two of its major climatic constraints, growing-season minimum temperatures and drought (SPEI index), across biomes and elevation gradients during two periods with different warming rates (1960-1980 vs. 1980-2000). We found a decrease in the correlations of minimum temperatures with growth, but a strengthening of drought-growth relationships. However, these patterns varied across biomes because correlations between growth and temperature decreased in temperate forests and woodland shrubland, while correlations between growth and SPEI increased in boreal forests and decreased in temperate forests. Differences in growth responsiveness to climate between the two periods were more marked for mid-latitude forests situated between 1200 and 1600 m. The slopes of the relationships between growth-temperature correlations and elevation decreased in late spring and midsummer. The slopes of the relationships between growth-drought correlations and elevation increased in temperate forests and woodland shrubland suggesting that drought impacts are “climbing” in these biomes. Temperature controls on forest growth are relaxing as the climate warms, while drought is becoming a more significant constraint for tree growth, particularly for mid-elevation forests and in drought-prone woodland and shrubland. The strengthening of drought-growth coupling should be considered in vegetation models to reduce the uncertainty on forest climate mitigation.In this study, brominated flame retardants (BFRs), including 13 polybrominated diphenyl ethers (PBDEs) and 17 novel brominated flame retardants (NBFRs) are determined in 18 species (including plankton, invertebrate, and fish) from Bohai Sea, China. Trophic transfer of these compounds is also assessed in the marine food web. Significant trophic magnification (p less then 0.01) for 11 PBDE congeners (BDE-17, BDE-28, BDE-47, BDE-49, BDE-66, BDE-85, BDE-99, BDE-100, BDE-153, BDE154 and BDE-183) is observed. No significant correlation is observed for BDE-138 (p = 0.06), and significant trophic dilution is observed for BDE-209 (p less then 0.0001). selleck chemical In PBDEs, BDE-66 has the highest TMF value of 3.9 (95% confidence interval (CI) 3.2-4.7), followed by BDE-47 (TMF 3.8, 95% CI 2.6-5.4) and BDE-28 (3.0, 2.2-4.1). For NBFRs, ATE, TBECH (include α- and β-isomer), PBBZ, TBCO (include α- and β-isomer), PBT, DPTE, HBBZ, PBBA, BTBPE, PBEB and HCDBCO are observed significant trophic magnification (p less then 0.01), significant trophic dilution is observed for BATE (p less then 0.