Self-assembly of N-heterocyclic carbenes on Au(111).

Although the self-assembly of organic ligands on gold has been dominated by sulfur-based ligands for decades, a new ligand class, N-heterocyclic carbenes (NHCs), has appeared as an interesting alternative. However, fundamental questions surrounding self-assembly of this new ligand remain unanswered. Herein, we describe the effect of NHC structure, surface coverage, and substrate temperature on mobility, thermal stability, NHC surface geometry, and self-assembly. Analysis of NHC adsorption and self-assembly by scanning tunneling microscopy and density functional theory have revealed the importance of NHC-surface interactions and attractive NHC-NHC interactions on NHC monolayer structures. A remarkable way these interactions manifest is the need for a threshold NHC surface coverage to produce upright, adatom-mediated adsorption motifs with low surface diffusion. NHC wingtip structure is also critical, with primary substituents leading to the formation of flat-lying NHC2Au complexes, which have high mobility when isolated, but self-assemble into stable ordered lattices at higher surface concentrations. These and other studies of NHC surface chemistry will be crucial for the success of these next-generation monolayers.

The haematological response to an iron injection amongst female athletes.

The aim of this study was to monitor the haematological response of female athletes with moderately low ferritin values to an iron injection. We measured the total haemoglobin mass of 11 female basketballers with a range of ferritin values who lived and trained together for the duration of the study (age 18+/-1, range 16-19 yrs), [Hb] 12.4+/-1.3, 11.5-16.1 g x dL; ferritin 35.6+/-15.6, 9-58 microg x L). A total dose of 2.5 mL Ferrum H was administered to six squad members who were matched with the remaining five controls based on ferritin measures obtained three weeks earlier. Venous blood samples were drawn weekly to obtain full blood counts, reticulocyte parameters as well as iron profiles. There was no change detected in any of the haematological parameters measured in the treatment group compared to controls. A repeated measures ANOVA (treatment x time) demonstrated that neither total haemoglobin mass (P = 0.91) nor [Hb] (P = 0.79) altered significantly between groups, whilst the mean haemoglobin content of reticulocytes also showed no response (P = 0.17). Because a positive haematological response is definitive evidence of impaired red cell production, our results indicate that none of the athletes were iron deficient at the time of the injection. This suggests that low ferritin values in trained female athletes are not always associated with impaired red cell production.