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Vilstrup Bendtsen posted an update 5 hours, 2 minutes ago
Chiral amino acid-derived formamides represent one of the most versatile components in multicomponent reactions. Herein, we describe a facile synthesis of Nβ-protected amino sulfenyl methyl formamides and sulfonyl methyl formamides via the Mannich reaction of Nα-protected amino alkyl thiols followed by oxidation using 3-chloroperbenzoic acid (m-CPBA). This protocol is applicable to a wide range of Fmoc- and Cbz-protected amino acids. Notably, the reaction provides high yield and retains the stereochemistry of the chiral center of the starting component.This paper presents an experimental investigation on the propagation of chemical grouting in a two-dimensional permeated fracture network with various aperture widths. As grouting engineering is often concealed in most experiments, the propagation of grout in fractures is not fully understood. UCL-TRO-1938 cell line The anisotropic permeability of geological masses with different aperture widths was found and has been investigated since 1960. The deflection flow effect was first found by Tian for groundwater flow in two groups of fractures with different aperture widths. Field grouting indicated that the grout propagates along a group of fractures with larger apertures that are longer while propagating a shorter distance along fractures with small apertures. This phenomenon implies a deflection for grout propagation in fractures with different aperture widths. The results of our study confirm this and indicate that there would be an anisotropy of grout propagation when the two groups of aperture widths are different. The water flow conditions also cause the difference in grout propagation length. When the aperture widths of the two groups of fractures are the same, the propagation shows symmetrical ellipse propagation. The results show the anisotropy of the grout increases as the aperture width ratio increases. This study helps in understanding the mechanism of chemical grouting in fractures with different apertures and flowing water and outlines some implications for grouting design in a fractured rock mass.In this work, fluorescence excitation-emission matrices (EEMs), in combination with the chemometric tool and parallel factor analysis (PARAFAC), have been proposed as an unexplored methodology to follow the removal of the fluorescent contaminants of emerging concern, fluoroquinolones (FQs). Ofloxacin, enrofloxacin, and sarafloxacin were degraded by different advanced oxidation processes employing simulated sunlight (hν) photolysis, H2O2/hν, and photo-Fenton. All experiments were performed in ultrapure water at three different pH values 2.8, 5.0, and 7.0. With the obvious advantage of multivariate analysis methods, EEM-PARAFAC allowed the monitoring of degradation from the overall substances (original and formed ones) through simultaneous, rapid, and cost-efficient fluorescence spectroscopy determinations. A five-component model was found to best fit the experimental data, allowing us to (i) describe the decay of the fluorescence signals of the three parent pollutants, (ii) follow the kinetics profile of FQ-like byproducts with similar EEM fingerprints than the original FQs, and (iii) observe the formation of two families of reaction intermediates with completely different EEMs. Results were finally correlated with high pressure liquid chromatography, total organic carbon, and toxicity tests on Escherichia coli, showing good agreement with all the studied techniques.Idiosyncratic drug reactions are unpredictable adverse reactions. Although most such adverse reactions appear to be immune mediated, their exact mechanism(s) remain elusive. The idiosyncratic drug reaction most associated with serious consequences is idiosyncratic drug-induced liver injury (IDILI). We have developed a mouse model of amodiaquine (AQ)-induced liver injury that reflects the clinical characteristics of IDILI in humans. This was accomplished by impairing immune tolerance by using PD-1-/- mice and an antibody against CTLA-4. PD-1 and CTLA-4 are known negative regulators of lymphocyte activation, which promote immune tolerance. Immune checkpoint inhibitors have become important tools for the treatment of cancer. However, as in our model, immune checkpoint inhibitors increase the risk of IDILI with drugs that have an incidence of causing liver injury. Agents such as 1-methyl-d-tryptophan (D-1-MT), an inhibitor of the immunosuppressive indoleamine 2,3-dioxygenase (IDO) enzyme, have also been proposed as anti-cancer treatments. Another possible risk factor for the induction of an immune response is the release of danger-associated molecular patterns (DAMPs). Acetaminophen (APAP) is known to cause acute liver injury, and it is likely to cause the release of DAMPs. Therefore, either of these agents could increase the risk of IDILI, although through different mechanisms. If true, then this would have clinical implications. We found that co-treatment with D-1-MT paradoxically decreased liver injury in our model, and although APAP appeared to slightly increase AQ-induced liver injury, the difference was not significant. Such results highlight the complexity of the immune response, which makes potential interactions difficult to predict.Spreading over porous substrates occurs in several processes including printing, cleaning, coating, and manufacturing of ceramic structures. For small drops, viscous and capillary forces are ultimately the predominant forces. The process typically undergoes three phases a first stage in which the droplet spreads, a second phase in which the area of contact with the solid substrate nearly remains constant, and a third stage in which the droplet retracts with its volume reaching zero finally. The objective of the investigation is to find the dynamics of spreading and absorption of the droplet using fundamentals while making relevant approximations to account for both radial and vertical dynamics. The proposed model requires minimal computational work. The results are compared with the published experimental data for the perfect wetting case, and are found to be in good agreement with detailed published experimental data for both droplet dynamics and dynamics of penetration in the porous substrate.