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plain landscapes, which cover one third of the global land area.The surface urban heat island (SUHI) is one of the most significant human-induced alterations to the Earth's surface climate and can aggravate health risks for city dwellers during heat waves. Although the SUHI effect has received growing attention, its diurnal cycles (i.e., the variations over the full 24 h within the diel cycle) are poorly understood because polar-orbiting satellites (e.g., Landsat Series, Sentinel, Terra, Aqua) only provide one or two observations over each repeat cycle (e.g., 16 days) with constant overpass time for the same area. Geostationary satellites provide high-frequency land surface temperature (LST) observations throughout the day and the night, and thereby offer unprecedented opportunities for exploring the diurnal cycles of SUHI. Here we examined how the SUHI intensity varied over the course of the diurnal cycle in the Boston Metropolitan Area using LST observations from the NOAA's latest generation of Geostationary Operational Environmental Satellites (GOES-R). GOES-R LST was HI intensity (-0.6-+0.9 °C) was commonly observed at 0000-0700 and 1700-2300. We also found different relationships between SUHI intensity and potential drivers within a diurnal cycle, characterized by the strongest correlation with impervious surface area and population size during the middle of the day, and with tree canopy cover at night. Our research highlights the great potential of the new-generation geostationary satellites in revealing the detailed diurnal variations of SUHI. Our findings have implications for informing urban planning and public health risk management.Drinking water treatment plants (DWTPs) face changes in raw water quality, which affect the formation of disinfection by-products. Several empirical modelling approaches have been reported in the literature, but most of them have been developed with lab-scale data, which may not be representative of real water systems. Therefore, the application of these models for real-time operation of DWTPs might be limited. At the present study, multiple linear regression (MLR) and multi-layer perceptrons (MLP) were benchmarked using field-scale data for predicting the THMs formation in a case-study DWTP in Barcelona, Spain. After fitting the studied models, MLR exhibited good fit with the validation data set (R2 = 0.88 and MAE = 4.0 μg·L-1) and described the most plausible input-output relationships with field-scale data. The MLR predictive model was incorporated into an environmental decision support system (EDSS) for assessing the THMs formation at two critical points of the distribution network. A Monte Carlo scheme was applied for quantifying uncertainty of model predictions at these points, considering low and high water quality scenarios and different degrees of treatment by an electrodialysis reversal process. The results show that the use of the proposed EDSS can help in real operation of complex drinking water systems, which face important changes in water quality throughout the year.Exposure to environmental phenols such as bisphenol A, benzophenones, 2-phenylphenol, triclosan, and triclocarban is of concern, because of their endocrine disrupting properties and broad application in consumer products. The current body burden of the 3-17-year-old population in Germany to these substances was assessed in first-morning void urine samples (N = 515-516) collected within the population-representative German Environmental Survey for Children and Adolescents 2014-2017 (GerES V). Bisphenol A was the most prominent phenol analysed here, ubiquitously found in almost all samples with a geometric mean (GM) concentration of 1.905 μg/L (1.669 μg/gcreatinine) and a maximum (MAX) urinary concentration of 399 μg/L. Benzophenone-3 and benzophenone-1 were quantified in 35% and 41% of the samples. GM was below the limit of quantification (LOQ) for benzophenone-3 and 0.559 μg/L (0.489 μg/gcrea) for benzophenone-1, MAX concentrations were 845 μg/L and 202 μg/L, respectively. In 16% of the samples triclosan was found in quantifiable amounts resulting in a GM below LOQ and a MAX concentration of 801 μg/L. Benzophenone-8, 2-phenylphenol and triclocarban were quantified in none or only 1% of the samples. Benzophenone-1 and -3 concentrations were found to be associated with frequent application of personal care products. A comparison with the previous cycle of the survey, GerES IV (2003-2006), showed a decrease of urinary bisphenol A concentrations, mainly in young children. Despite this decrease, the concentration of bisphenol A exceeded the human biomonitoring (HBM) value HBM-I of 0.1 mg/L in 0.11% of the samples. For triclosan, all urinary concentrations were well below the HBM-I value of 2 mg/L. To minimise environmental health risks, it is therefore necessary to maintain a further declining trend for bisphenol A and continue monitoring the exposure to environmental phenols, as well as to monitor substitutes such as bisphenol F and S.Thyroid hormones act on almost every tissue in the body to promote catabolism in cells and are important for regulating many biological processes. Accurate quantification of endogenous thyroid hormones has become essential for clinical and non-clinical applications in the development of new drugs according to the OECD Guideline (2018). However, there are difficulties in quantitative analysis of thyroid hormones because no analyte-free biological matrices are available for analysis of endogenous substances. In this study, surrogate matrix and surrogate analyte methods were compared and validated to quantify endogenous triiodothyronine (T3) and thyroxine (T4) in rat serum using LC-MS/MS. Separation of analytes was performed using an Xbridge™ C18 (2.1 × 50 mm, 2.5 μm) column. In the surrogate matrix, 3,3'5-triiodo- l-thyronine-13C6 (cT3) and l-thyroxine-13C6 (cT4) were used as the internal standard (IS), and in the surrogate analyte, l-3,3'-diiodothyronine-13C6 (cT2) was used as the IS. The mobile phases consisted of 0.1 % acetic acid in purified water (A) and 0.1 % acetic acid in acetonitrile (B). Both analytical methods were suitable for selectivity, matrix effect, carryover, lower limit of quantification, linearity, accuracy, precision, recovery, stability and parallelism. The surrogate matrix method was more accurate than using the surrogate analyte method, including evaluation of parallelism at low concentrations. Additionally, the surrogate matrix is cost-effective for T3 and T4 analysis in biological samples because it consists only of deionized water. 4-Methylumbelliferone supplier However, surrogate analytes difficult to evaluate parallelism by obtaining response factors for mass spectrometric signal differences between the actual and surrogate analytes. Therefore, the results of this study indicate that it is more cost-effective to use the surrogate matrix method for endogenous thyroid hormone, T3 and T4, analysis in biological samples.

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