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Anker Hampton posted an update 6 months, 2 weeks ago
To evaluate the human health risks attributed by organophosphate ester (OPE) exposure, it is very important to estimate the daily intakes (DIs) of OPEs in human. In this study, the DIs of OPEs were estimated using a simplified one-compartment toxicokinetic model based on their total clearance rates in human and their whole blood concentrations. Thirty paired human whole blood and plasma samples were collected from participants in Hengshui, Hebei Province, China. The detection frequencies of most OPEs in the whole blood were lower than 50.0%. Thus, the OPE levels in whole blood were converted from the corresponding plasma levels using the fractions of OPEs in plasma (Fp), which were estimated from an in vitro partition assay and the values were in the range of 0.52-0.98. The measured whole blood concentrations of triphenyl phosphate (TPHP) and tris(chloroethyl) phosphate (TCEP) were comparable to those converted from the plasma concentrations, suggesting that the conversion method was reliable. The estimated total DIs of TPHP, TCEP, and tris(2-chloroisopropyl) phosphate were 1-30 times of those derived by the external exposure method, which usually excluded many exposure sources. Staurosporine The estimated human health risks based on the DIs indicated that the carcinogenic and non-carcinogenic effects of OPEs for the participants in Hengshui, Hebei Province, China, were negligible. This study recommended a more reliable and simpler method to estimate the human health risks attributed to the exposure of OPEs. The frequent occurrence of toxin-producing cyanobacteria blooms driven by anthropogenic eutrophication has become a major threat to aquaculture ecosystems worldwide. In this study, the behavior of M. aeruginosa cells during flocs storage period of 6 days was first investigated after pre-oxidation and coagulation of Fe2+/PS. Fe2+/PS achieved a superior removal efficiency of 90.7% for OD680 and 90.4% for chl-a. The contents of extracellular MCs in the pre-oxidation and coagulation system were significantly (P less then 0.05) lower than those in the control. A significant (P less then 0.05) difference in intracellular protein between the control and the coagulated systems was observed. Three-dimensional fluorescence excitation emission matrix (EEM) was employed to investigate the variations in extracellular organic matter (EOM) during flocs storage. The results indicated the presence of four peaks, representing protein-like substances, intermediate dissolved microbial metabolites, fulvic and humic-like compounds in the Fe2+/PS process. And the intensities of four peaks were all decreased in the Fe2+/PS system compared to those in the control. A low level of accumulated residual Fe of 0.28 mg/L was observed without posing potential environmental risk. The results showed that the M. aeruginosa cells were under stressful conditions after 3-d storage due to the decomposition of extracellular polymeric substances (EPSs) and the insufficient supply of nutrients. However, SEM results indicated that no significant alteration in cell morphology was observed. Therefore, with high removal of M. aeruginosa, low MCs concentrations, and trivial cell damage, the Fe2+/PS preoxidation-coagulation was proved to be an environmental-friendly method for cyanobacteria removal without yielding serious secondary pollution. This work will contribute to better understanding and managing the cyanobacteria-laden aquaculture water after pre-oxidation and coagulation. Ratcliff and McKoon (2018) proposed integrated diffusion models for numerosity judgments in which a numerosity representation provides evidence used to drive the decision process. We extend this modeling framework to examine the interaction of non-numeric perceptual variables with numerosity by assuming that drift rate and non-decision time are functions of those variables. Four experiments were conducted with two different types of stimuli a single array of intermingled blue and yellow dots in which both numerosity and dot area vary over trials and two side-by-side arrays of dots in which numerosity, dot area, and convex hull vary over trials. The tasks were to decide whether there were more blue or yellow dots (two experiments), more dots on which side, or which dots have a larger total area. Development of models started from the principled models in Ratcliff and McKoon (2018) and became somewhat ad hoc as we attempted to capture unexpected patterns induced by the conflict between numerosity and perceptual variables. In the three tasks involving numerosity judgments, the effects of the non-numeric variables were moderated by the number of dots. Under a high conflict, judgments were dominated by perceptual variables and produced an unexpected shift in the leading edge of the reaction time (RT) distributions. Although the resulting models were able to predict most of the accuracy and RT patterns, the models were not able to completely capture this shift in the RT distributions. However, when subjects judged area, numerosity affected perceptual judgments but there was no leading edge effect. Based on the results, it appears that the integrated diffusion models provide an effective framework to study the role of numerical and perceptual variables in numerosity tasks and their context-dependency. Ensembles of protein aggregates are characterized by a nano- and micro-scale heterogeneity of the species. This diversity translates into a variety of effects that protein aggregates may have in biological systems, both in connection to neurodegenerative diseases and immunogenic risk of protein drug products. Moreover, this naturally occurring variety offers unique opportunities in the field of protein-based biomaterials. In the above-mentioned fields, the isolation and structural analysis of the different amyloid types within the same ensemble remain a priority, still representing a significant experimental challenge. Here we address such complexity in the case of insulin for its relevance as biopharmaceutical and its involvement in insulin-derived amyloidosis. By combining Fourier Transform Infrared Microscopy (micro-FTIR) and fluorescence lifetime imaging microscopy (FLIM) we show the occurrence, within the same ensemble of insulin protein aggregates, of a variable β-structure architecture and content not only dependent on the species analyzed (spherulites or fibrils), but also on the position within a single spherulite at submicron scale.
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