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Chiral packing of ligands on the surface of nanoparticles (NPs) is of fundamental and practical importance, as it determines how NPs interact with each other and with the molecular world. Herein, for gold nanorods (NRs) capped with end‐grafted nonchiral polymer ligands, we show a new mechanism of chiral surface patterning. Under poor solvency conditions, a smooth polymer layer segregates into helicoidally organized surface‐pinned micelles (patches). The helicoidal morphology is dictated by the polymer grafting density and the ratio of the polymer ligand length to nanorod radius. Outside this specific parameter space, a range of polymer surface structures was observed, including random, shish‐kebab, and hybrid patches, as well as a smooth polymer layer. We characterize polymer surface morphology by theoretical and experimental state diagrams. The helicoidally organized polymer patches on the NR surface can be used as a template for the helicoidal organization of other NPs, masked synthesis on the NR surface, as well as the exploration of new NP self‐assembly modes. Gold nanorods, end‐grafted with achiral polymer ligands, show a new mechanism of chiral surface patterning giving a helicoidal morphology. This morphology is dictated by the relationship between the polymer grafting density and the ratio of the polymer length to the nanorod radius. [ABSTRACT FROM AUTHOR]

The resemblance between colloidal and molecular polymerization reactions is very useful in fundamental studies of polymerization reactions, as well as in the development of new nanoscale systems with desired properties. Future applications of colloidal polymers will require nanoparticle ensembles with a high degree of complexity that can be realized by hetero-assembly of NPs with different dimensions, shapes, and compositions. A method has been developed to apply strategies from molecular copolymerization to the co-assembly of gold nanorods with different dimensions into random and block copolymer structures (plasmonic copolymers). The approach was extended to the co-assembly of random copolymers of gold and palladium nanorods. A kinetic model validated and further expanded the kinetic theories developed for molecular copolymerization reactions. [ABSTRACT FROM AUTHOR]

Objective: This study addresses the following research questions: (1) Is race a predictor of obtaining a referral for coronary angiography (CA) among patients who are appropriate candidates for the procedure? (2) Is there a race disparity in obtaining CA among patients who obtain a referral for the procedure?Study Setting: Three community hospitals in Baltimore, Maryland.Study Design: We abstracted hospital records of 7,927 patients from three hospitals to identify 2,653 patients who were candidates for CA. Patients were contacted by telephone to determine if they received a referral for CA. Logistic regression was used to assess whether racial differences in obtaining a referral were affected by adjustment for several potential confounders. A second set of analyses examined race differences in use of the procedure among a subsample of patients that obtained a referral.Principal Findings: After controlling for having been hospitalized at a hospital with in-house catheterization facilities, ACC/AHA (American College of Cardiology/American Heart Association) classification, sex, age, and health insurance status, race remained a significant determinant of referral (OR = 3.0, p < .05). Additionally, we found no significant race differences in receipt of the procedure among patients who obtained a referral.Conclusions: Our results demonstrate that race differences in utilization of CA tend to occur during the process of determining the course of treatment. Once a referral is obtained, African American patients are not less likely than white patients to follow through with the procedure. Thus, future research should seek to better understand the process by which the decision is made to refer or not refer patients. [ABSTRACT FROM AUTHOR]

The self‐assembly of colloidal analogues of molecular copolymers can greatly benefit fundamental studies of molecular copolymerization and nanotechnology. In their Communication on page 2648 ff., K. Liu, E. Kumacheva, et al. present microscopy and spectroscopy analyses to develop design rules and a kinetic model for the growth of colloidal random and block copolymers made from plasmonic nanorods with different lengths and compositions. [ABSTRACT FROM AUTHOR]

Die Selbstorganisation kolloidaler Analoga von molekularen Copolymeren kann grundlegende Erkenntnisse für die Gebiete der molekularen Copolymerisation und der Nanotechnologie liefern. In ihrer Zuschrift auf S. 2686 ff. präsentieren K. Liu, E. Kumacheva et al. eine mikroskopische und spektroskopische Analyse, mit deren Hilfe sie Design ‐ Regeln und ein kinetisches Modell für das Wachstum kolloidaler Zufalls ‐ und Blockcopolymere aus plasmonischen Nanostäben unterschiedlicher Länge und Zusammensetzung formulieren. [ABSTRACT FROM AUTHOR]