Storm events play a crucial role in organic matter transport within watersheds and can increase the concentration and alter the composition of NOMs and DBP formation potential. To assess the impact that storm events can have on drinking water quality, samples were collected and analyzed across four storm events in the Neversink River, Catskill region, New York in 2019 and 2022. Source water natural organic matter (NOM) was characterized, and the change of NOM quality was evaluated due to storm impacts. During storm events, a high level of NOM mobilization is initiated by heavy precipitation causing overland flow and a rise in the water table. In this way, storms result in increased access to stored NOM pools that are generated during inter-storm periods. A significant correlation was observed between several organic water quality parameters such as UV absorbance (UV), dissolved organic carbon (DOC) and chlorine demand. Precursors for the total trihalomethanes (TTHM), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) exhibited comparable patterns with UV, DOC, and chlorine demand for four storms. Despite the potential for increased dilution resulting from higher discharges, all organic water quality parameters, including yields of disinfection byproducts (i.e., DBP precursors), exhibited elevated concentrations during periods of higher flows. Three of the four storms showed hysteresis patterns with higher observed concentrations of organic constituents in the falling limb of the hydrographs. Precursors for the nitrogenous DBPs (N-DBPs) were proportional to the DOC for all four storms. The coefficient of determination (R) for TTHM, DCAA, TCAA with UV is higher (R 0.92-0.98) than corresponding correlations with DOC (R 0.89-0.92). The R for UV showed the following hierarchy: DCAA≈TCAA>TTHM. Additionally, the R for DOC and specific ultraviolet absorbance (SUVA) had the following hierarchy: DCAA>TCAA>TTHM and TCAA>DCAA>TTHM respectively. A significant correlation between UV and DOC (R = 0.99) for all storms was observed. Chlorine demand also yielded a strong correlation (R = 0.91∼0.98) with UV and DOC. This research indicates that a significant and disproportionate export of NOM to source waters occurs during storm events compared to baseflow conditions. Consequently, it is recommended for drinking water treatment facilities to reassess chlorine dosages during these events. Treatment plants can employ UV as a tool to determine appropriate chlorine dosages, aiming to mitigate DBP formation in treated waters.
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http://dx.doi.org/10.1016/j.watres.2024.121445 | DOI Listing |
Am J Biol Anthropol
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Primate Models for Behavioural Evolution Lab, Institute of Human Sciences, University of Oxford, Oxford, UK.
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Public Health, Khamis Mushayt General Hospital, Khamis Mushait, Saudi Arabia.
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A variety of autoimmune disorders are associated with an increased risk of thrombosis. Previous studies have suggested combined therapy of heparin and therapeutic plasma exchange (TPE) with fresh frozen plasma (FFP) as the replacement fluid is beneficial in some cases of acute flare-up of autoimmune diseases complicated by thrombotic events. Nevertheless, it remains unknown whether clinicians do more harm than good by exposing patients to a "thrombotic storm" through simultaneous administration of heparin and the clotting factors in the FFP during TPE.
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December 2024
Population Policy and Practice Department, UCL Great Ormond Street Institute of Child Health, University College London, London, UK; Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK. Electronic address:
Lancet Respir Med
December 2024
Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Manchester, UK. Electronic address:
Background: The goal of cystic fibrosis transmembrane conductance regulator (CFTR) modulators is to reach normal CFTR function in people with cystic fibrosis. Vanzacaftor-tezacaftor-deutivacaftor restored CFTR function in vitro and in phase 2 trials in participants aged 18 years and older resulting in improvements in CFTR function, as measured by sweat chloride concentrations and lung function as measured by spirometry. We aimed to evaluate the efficacy and safety of vanzacaftor-tezacaftor-deutivacaftor compared with standard of care elexacaftor-tezacaftor-ivacaftor in individuals with cystic fibrosis aged 12 years and older.
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