New insights into the formation chemistry of chalcogenate-protected metal nanoparticles (NPs) synthesized via the well-known Brust-Schiffrin two-phase method are presented here. On the basis of Raman, NMR, and surface plasmon resonance characterizations, it is concluded that, before the formation of any metal-chalcogen bonds, metal nucleation centers/NPs are first formed inside the inverse micelles of the tetrabutylammonium bromide in the organic solvent, where the metal ions are reduced by NaBH(4). The ensuing formation of the metal-chalcogen bonds between the naked metal NPs inside the micelles and the organo-chalcogen ligands in the organic solvent is the mechanism by which the further growth of the metal core can be controlled. This proposed mechanism is further examined in the formation of Ag and Cu NPs.

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Objective: This study evaluates the relationship between hospital and surgeon volumes of peritrochanteric hip fracture fixation and complication rates.Methods: Adults (60 years of age or older) who underwent surgical fixation for closed peritrochanteric fractures from 2009 to 2015 were identified using International Classification of Diseases 9 and 10 Clinical Modification and Procedural codes in the New York Statewide Planning and Research Cooperative System database. Readmission, reoperations, in-hospital mortality, and other adverse events were compared across surgeon and facility volumes. Statistical significance was set at P , 0.05.Results: A total of 29,656 patients were included in the study. Lowvolume (LV) facilities had higher rates of readmission [hazard ratio (HR) 1.07, 95% confidence interval (CI), 1.05-1.17], pneumonia (HR 1.36, 95% CI, 1.22-1.51), wound complications (HR 1.24, 95% CI, 1.03-1.49), and mortality (HR 1.15, 95% CI, 1.04-1.27) but lower rates of acute renal failure (HR 0.90, 95% CI, 0.83-0.98), deep vein thrombosis (HR 0.66, 95% CI, 0.55-0.78), and acute respiratory failure (HR 0.77, 95% CI, 0.62-0.95) than high-volume (HV) facilities. Patients treated by LV surgeons had lower rates of readmission (HR 0.92, 95% CI, 0.87-0.97) and deep vein thrombosis (HR 0.78, 95% CI, 0.66-0.94) but higher rates of acute renal failure (HR 1.13, 95% CI, 1.04-1.22) than those treated by HV surgeons.Conclusions: There are increased rates of mortality, readmission, and certain complications when peritrochanteric femur fractures are surgically managed at LV hospitals compared with those managed at HV hospitals. Thus, the benefit of a high-volume surgical facility is apparent in mortality and readmissions but not all complications. There was no significant decrease in complications if fixation was performed by HV surgeons relative to LV surgeons.