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We report the synthesis and characterization of novel anionic arylfluoroborate, three-coordinate ligated arylcopper(I) and cationic ligated copper(I) complexes. We show through in situ 19F NMR monitoring that neutral arylboronate ester is more kinetically competent than anionic arylfluoroborate for transmetalation with (PN)CuF (PN = o-(di-tert-butylphosphino)-N,N-dimethylaniline). The transmetalation of the neutral arylboronate ester proceeds via a two-step process involving a cationic copper(I) species wherein an anionic arylfluoroborate is generated in situ as a competent aryl group transferring reagent.

Ventilator-associated pneumonia (VAP) develops in up to 25% of patients following cardiac surgery. Colonization of the endotracheal tube (ETT) contributes to VAP. The PneuX ETT has been shown to halve VAP in high-risk patients undergoing cardiac surgery. This article reports on the secondary analysis of bacterial colonization in relation to VAP between the PneuX and standard ETTs.In this randomized controlled trial, patients were randomized on a 1:1 basis to Group A (PneuX ET, N=120) or Group B (standard ETT, N=120). Patients aged70 years with or without impaired left ventricular function (50%) undergoing elective and urgent cardiac surgery were included in this study. Incidence of postoperative VAP and analysis of bacterial colonization within the ETT (N=234) were measured for patients requiring24 h, 24-48 h and48 h of intubation.Baseline patient demographics were comparable. VAP was lower in Group A compared with Group B (10.8% vs 21%; P=0.03). The incidence of VAP was lower at each time point for Group A. There was a lower incidence of ETT colonization in Group A for patients needing48 h of intubation. There was no difference in the type of bacterial colonization (P=0.5) or the mean number of colony-forming units [4.35x10Colonization of the ETT does not seem to play an important role in early-onset VAP. There is a tendency for reduced colonization in the PneuX ETT with longer intubation times. This may have an impact on reducing the incidence of late-onset VAP.

Black objects are sometimes associated with black carbon, while shiny, highly reflecting surfaces are typically associated with metals. Here, we discuss several objects in everyday life that upon use take on a black color that is unlikely to be due to black carbon. We propose that this black color is caused by the formation of metallic nanoparticles from abrasion processes. We support this hypothesis using Mie theory and the fact that spherical metal particles are only shiny or bright if the imaginary part of their refractive index and its product with the particle size-parameter are both larger than three. While this is commonly true for bulk metals, the second condition is generally not fulfilled for metallic nanoparticles, and hence, such particles become highly absorbing, i.e., black. For the black grime accumulated on bicycle drivetrains and climbing ropes, we detected metal nanoparticles with electron microscopy, which likely originated from mechanical abrasion processes during use.

Iodination of remote aryl C–H bonds has been achieved using palladium acetate as the catalyst and iodoacetate (IOAc) as the oxidant. Systematic kinetic isotope studies imply a mechanistic regime shift as the number of bonds separating the directing heteroatom and the target C–H bond increases. Both isotope and electronic effects observed in remote C–H bond activation are consistent with an electrophilic palladation pathway in which the initial palladation is slower than the C–H bond cleavage.